- test-drb@ccmp.vtda.org - classiccmp.org

by ajp166＠bellatlantic.net

> >Subject: Small SBC kits for Christmas! > From: "Matt Lichtenberg" <kerobaros at gmail.com> > Date: Sat, 15 Dec 2007 08:21:28 -0600 > To: cctalk at classiccmp.org > >So, every year I like to get myself a little something; this year, I'm >probably going to be getting a new computer (outside the realms of >this list), but I'd also like to get some kind of single-board kit >that I can work on. > >I'd like something along the lines of a ZX-81 kit, although it looks >like those are selling for somewhere around $250, when you can find >one. SpareTimeGizmos' Elf 2000 kit also looks fantastic, but I don't >have an 1802 or an 1861 to use in the thing, and I'd rather not hunt >any down. (If anyone wants to get rid of theirs, though, let me know. >*grin*) The Elf200 is excellent and there is a yahoo group for it as well. Finding 1802s is generally easy. the 1861 is a different can of worms but Bob solved that with a tiny board that emulates it. See the Spare Time Gizmos site for details. No you can't have mine! >Has anyone seen any similar kits out there? They don't have to be >useful for anything, just fun to play with, and not horribly difficult >to put together. I can solder fairly well, and I'm mean with a >multimeter, but I don't have the money for my own oscilloscope; I just >use other peoples' when they're not looking. Thanks, folks! If you hunt around the net there are SBC of all sorts. Allison >~Matt

18 years, 8 months

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4004 and IC history / was Re: Vintage computer photogallery

by RodSmallwood＠mail.ediconsulting.co.uk

It could be him, but its over thirty years ago and of course remember I him as he was not as he maybe now. I worked for the Terminals Product Line and sold VT100's and LA36's to resellers and OEM's in the UK. The target margin per unit may not have been reached. However the volume was so high and the economies of scale such that over all DEC made lots of profit from what became the industry standard. Rod -----Original Message----- From: cctech-bounces at classiccmp.org [mailto:cctech-bounces at classiccmp.org] On Behalf Of Tore Sinding Bekkedal Sent: 16 December 2007 18:56 To: General Discussion: On-Topic and Off-Topic Posts Subject: RE: 4004 and IC history / was Re: Vintage computer photogallery On Thu, 2007-10-18 at 13:04 +0100, Rod Smallwood wrote: > The design of the VT100 was done by one engineer who I met but I > cannot recall his name. I believe you may be referring to Mike Leis. I snapped a photo of him at a DEC reunion at The Mill: http://gunkies.org/photos/mill/big/img_3513.jpg Amongst other things, he told me that DEC considered the VT100 to be a failure, since it never met the profit margin outlined in the project proposal. The main reason they created the VT100 was because the VT52 was quite hard to mass produce automatically. -Tore

18 years, 8 months

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Homebrew Drum Computer (magnetic heads)

by ajp166＠bellatlantic.net

> >Subject: Homebrew Drum Computer (magnetic heads) > From: Robert Nansel <bnansel at bigpond.net.au> > Date: Mon, 17 Dec 2007 09:31:49 +1030 > To: cctalk at classiccmp.org > >I think I might have a whack at making R/W heads using small ferrite >cores/beads, the kind used in radio work. > >My plan is to string several cores up on a straight brass rod with a >snug fit to their I.D., then bed the whole lot in wax and remove the >rod. Next I'll use an abrasive <mumble 1> to grind a tiny V-notch >from the inside of the cores, taking care not to break through the >outer diameter. > >After removing the cores from the wax I'll wind <mumble 2> turns of ><mumble 3> gauge magnet wire on them, fixed in place with super >glue. Then I would re-bed them in more wax, this time with the coils >down and the internal notches up. The cores would be almost >completely embedded in the wax to provide strength for the fInal >step, grinding a flat very slowly from the outside until the sharp >end of the notch is exposed for each core. This makes the gap. > >I'll remove them from the wax and mount them on <mumble 4> blocks >with <mumble 5> screw adjustments. > >As for the drum part, I think I'll be best off with a disk instead, >perhaps a 14" washing machine platter and spindle from a 3000RPM ><mumble 6> Gonkulator. > >So, aside from the mumbles, does this sound like a workable plan? Ah no. the gaps have to be narrow less than .001". that hs been done two peice ferrite heads (half beads) with oe side of the magnetic circuit filled with .001" thick brass shim stock. Or you could pull the heads from a number of old floppies. The 14" platter is a good source for media. Allison >-Bobby > > >> Fri Dec 14 14:22 Gary Oliver go at ao.com said: >> >> I have a reference somewhere for a drum project from the 40s that used >> what would now be simple machine-shop procedures (assuming one had a >> small drill-mill and lathe) to fashion a small drum of a few k-bit >> capacity. I'll try to dig that out and send it along. I was sort of >> planning to do something along this line myself at some point during >> "retirement" (which won't be for a few years, I suspect.) I've >> acquired >> a few of the components for fabricating the drum and will give it a >> "whirl" some day. I was definitely NOT planning to make a flying head >> device and to keep it simple enough I could fabricate a few heads from >> "first principles."

18 years, 8 months

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KayPro II keyboard schematic?

by ajp166＠bellatlantic.net

> >Subject: Re: KayPro II keyboard schematic? > From: ard at p850ug1.demon.co.uk (Tony Duell) > Date: Sun, 16 Dec 2007 22:17:22 +0000 (GMT) > To: cctalk at classiccmp.org > >> > What was used inside the Kaypro to receive the keyboard data? >> >> Z80 SIO, at least on the -II and -4. > >Drat! It could be async or syunc, since that chip can be configured to >handle eithr format. But I'll be t it's the former. Its async, I posted it was Async, SIO/DART yesterday. It's levels are TTL to save RS232 conversion and power needed for negative supply. It's an easy keyboard to talk to via serial. I have two Kaypros and a spare keyboard. its not rocket science. Allsion > >-tony

18 years, 8 months

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Homebrew Drum Computer (magnetic heads)

by bnansel＠bigpond.net.au

I think I might have a whack at making R/W heads using small ferrite cores/beads, the kind used in radio work. My plan is to string several cores up on a straight brass rod with a snug fit to their I.D., then bed the whole lot in wax and remove the rod. Next I'll use an abrasive <mumble 1> to grind a tiny V-notch >from the inside of the cores, taking care not to break through the outer diameter. After removing the cores from the wax I'll wind <mumble 2> turns of <mumble 3> gauge magnet wire on them, fixed in place with super glue. Then I would re-bed them in more wax, this time with the coils down and the internal notches up. The cores would be almost completely embedded in the wax to provide strength for the fInal step, grinding a flat very slowly from the outside until the sharp end of the notch is exposed for each core. This makes the gap. I'll remove them from the wax and mount them on <mumble 4> blocks with <mumble 5> screw adjustments. As for the drum part, I think I'll be best off with a disk instead, perhaps a 14" washing machine platter and spindle from a 3000RPM <mumble 6> Gonkulator. So, aside from the mumbles, does this sound like a workable plan? -Bobby > Fri Dec 14 14:22 Gary Oliver go at ao.com said: > > I have a reference somewhere for a drum project from the 40s that used > what would now be simple machine-shop procedures (assuming one had a > small drill-mill and lathe) to fashion a small drum of a few k-bit > capacity. I'll try to dig that out and send it along. I was sort of > planning to do something along this line myself at some point during > "retirement" (which won't be for a few years, I suspect.) I've > acquired > a few of the components for fabricating the drum and will give it a > "whirl" some day. I was definitely NOT planning to make a flying head > device and to keep it simple enough I could fabricate a few heads from > "first principles."

18 years, 8 months

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xt/370 e-mail problem and stacked memory chips illustrated

by michaelryan＠mindspring.com

I have added a few new pictures to the xt/370 web site showing the stacked (and non-stacked) versions of the MCM66128L20, as well as two other examples of IBM engineering that employed stacked chips (AT motherboard and PC memory card) in the early 1980's. There are 36 pairs on the AT board to get 512K and 18 pairs on the memory card to get 64K. Obviously, these chips have different pinouts (at least select). The url is:- www.xt370.net click on the link to the left, 'Memory Technology' The question a data sheet might answer is:- does one of the new MCM66128L20 parts replace one of the old stacked pairs? --- also: -- >Subject: Re: Someone in search of XT/370 software >To: "General Discussion: On-Topic Posts Only" <cctech at classiccmp.org> >He's on the list. I have at least some of VM/PC, but when I tried to >email him to let him know, I got an autoresponse from a white-list >agent, which sent me to an unresponsive URL. It was sufficiently >irritating that I figured it wasn't worth pursuing further. >Seriously, folks, if you're going to ask for help, don't make it >impossible for people to give. >ok >bear Bear's criticism is well-founded. I believe I have corrected the problem; I did receive the e-mails and have responded off-list. At any rate, I greatly appreciate the interest and am sorry for the inconvenience. Mike

18 years, 8 months

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Homebrew Drum Computer

by ajp166＠bellatlantic.net

> >Subject: Re: Homebrew Drum Computer > From: ard at p850ug1.demon.co.uk (Tony Duell) > Date: Sat, 15 Dec 2007 23:29:12 +0000 (GMT) > To: cctalk at classiccmp.org > >> >> I thought of this, too. So far I haven't found an online source of >> them (Google search terms: "glass delay line" OR "quartz delay line" >> OR "ultrasonic delay line" TV PAL OR NTSC). > >I didn't think the NTSC system used a delay line at the receiver, but I >must admit I've never repaired a US TV set. Yes they did/do but is was not ultrasonic. The common ones were basically the same as LONG (4.5us?) transmission lines. They would be hard to find. Allison >It's not a common component for spares companies to stock, simply because >it rarely fails. And of course more modern TVs used IC delay lines, which >are not what we want here. > >When I wanted one, I went to an (alas long-gone) TV repair shop that also >sold compoennts. No, they didn't keep them in stock, but the owner found >a scrap PCB with a delay line on it. Needless to say that was acceptable. > >-tony

18 years, 8 months

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KayPro II keyboard schematic?

by ajp166＠bellatlantic.net

> >Subject: KayPro II keyboard schematic? > From: "Andrew Lynch" <lynchaj at yahoo.com> > Date: Thu, 13 Dec 2007 21:55:51 -0500 > To: <cctalk at classiccmp.org> > >Hi, >I recently bought a KayPro II keyboard. It contains a nice Keytronics >mechanical keyboard and really nice case. I'd like to convert it to a >parallel ASCII keyboard or just reuse its case but was wondering if anyone >had the schematics? > >Please let me know if you have the KapPro II keyboard schematics. Thanks! It has an 8048 uP if memory serves and the output is TTL level serial ASCII. Making it put out parallel would be a major hackup including reprogramming an 8748. Allison >Andrew Lynch

18 years, 8 months

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Quick survey

by cclist＠sydex.com

On 16 Dec 2007 at 9:06 dwight elvey <dkelvey at hotmail.com> > These are all 5.25inch. As far as I know, 10 sectored was > the most common. I don't know of any that used 16 sectored > and never heard of 9 sectored. The Vector Graphic systems all used 16-sector media and I've seen a few others systems as well. So, I'd be safe by generalizing that 8" 32-sector and 5.25" 10- and 16-sector covers just about all of the hard-sector media in common use? Does anyone know of any other "common" 8" hard-sector media? Thanks, Chuck

18 years, 8 months

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Small SBC kits for Christmas!

by cclist＠sydex.com

From: "Matt Lichtenberg" <kerobaros at gmail.com> Date: Sat, 15 Dec 2007 08:21:28 -0600 While not vintage (but then, is any modern kit really "vintage"?), TI has a very slick and inexpensive gizmo for their MSP-430 16-bit microcontroller. $20 bucks for a USB stick including programmer and processor; $10 for additional uC "heads". Might be a kick to fool around with: http://focus.ti.com/docs/toolsw/folders/print/ez430-f2013.html Cheers, Chuck

18 years, 8 months

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cctalk Digest, Vol 52, Issue 32

by cclist＠sydex.com

On Sat, 15 Dec 2007 10:36:39 +0100 (CET) > From: Christian Corti <cc at corti-net.de> > All the drums that I have seen have fixed heads. There are adjusting > screws for the distance between head and surface, but the head itself is > then fixed with another screw after adjusting (we had to do this on the > drum of our second LGP-30). Univac made extensive use of flying head drums during the 1960's. Systems as late as the 1108 used them. AFAIK, they all had "FH" prefixes to identify them as such. Bitsavers has the manual on the one I used on the 1108, the FH-880: http://www.bitsavers.org/pdf/univac/1107/UT-2560_FH- 880_Drum_Dec61.pdf IIRC, the FH-880 spun quite fast. On the other hand, the "big drum" on the 1108, the FASTRAND II, was a slow sewer-pipe of a monster. Here's a document that accurately describes it: http://www.fourmilab.ch/documents/univac/fastrand.html IIRC, the head movement was accomplished through an system of levers connected to solenoids that directly converted a binary code to a physical position. Regarding magnetostrictive delay line, bitsavers also has a collection of PB250 documents that might be worth a perusal: http://www.bitsavers.org/pdf/packardBell/PB-250/ Hope this helps, Chuck

18 years, 8 months

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Homebrew Drum Computer Delay Lines

by dkelvey＠hotmail.com

> From: bnansel at bigpond.net.au > > I've come across a reference to a reverb unit made with a garden > hose, speaker, and microphone. Would something as bone-headed as > this work as a data delay line? > > I've read that mercury was used in delay lines because it was a > better impedance match with quartz transducers, but wouldn't water > work nearly as well? Everything would need to be kept at a constant > temperature, and no doubt there would be some dispersion of the > compression waves. It's my understanding that a lot of materials > were tried for delay lines, but that mercury was the "best." > Hi The primary reason for mercury was the slow propagation time, not impedance. The slower, the more bits per length. Mechanical transformers are not all that hard to create. Early programmable calculators use a different mode of transmission. They use rotation of a wire. The twisting goes slower along the wire than a compression wave because it is the rotational inertia compared to the spring of the wire. Compressional waves tend to travel faster. In something like mercury, being a fluid, can only transmit compressional waves ( except other surface waves like ocean waves ). A wire can use either compressional or rotational. The rotational is slower and can hold more date for distance. The important thing for any of these is absorbing any reflection. This means that impedance matching and possible dampening will make all the difference. Surface can have vertical as well as shear waves but these are harder to control. The rotational wave is similar to a shear wave. Dwight _________________________________________________________________ Get the power of Windows + Web with the new Windows Live. http://www.windowslive.com?ocid=TXT_TAGHM_Wave2_powerofwindows_122007

18 years, 8 months

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any idea how to find old diamond edge 3d card?

by brad＠heeltoe.com

can anyone point me to a place to find an old "diamond edge 3d" graphics card? I specifically want one with the sega controller ports and a copy of virtua fighter. I looked on ebay - no luck. anyone have any ideas? any good places for ancient (like 1995) graphics cards? -brad

18 years, 8 months

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4004 and IC history / was Re: Vintage computer photogallery

by RodSmallwood＠mail.ediconsulting.co.uk

My memory may be at fault here but that sounds like it. A quad board ... I can't recall any yellow handles. It did have the standard DEC 20mA ASR 33 conector on a bit of short grey cable hanging off the top of the board. Other early sightings at DEC VT100 prototype . Wire wrap board mounted on a piece of thick plywood. Another similar bit of plywood on top with the monitor out of a VT52 perched on it. A third bit of plywood held the keyboard. A PSU (I know not whence that came) and an Intel MDS. (8 inch Floppy based in a blue box.) So I asked the inevitable 'Why all the wood' 'It doesn't short anything out came the reply' The design of the VT100 was done by one engineer who I met but I cannot recall his name. The case was the work of an industrial designer. We all thought the case was really smart LA36 prototype another wirewrap wonder with the print mech screwed to a board. LA180 prototype as LA-36 but with the wooden board clamped to the bench to stop it leaping about. Rod Smallwood -----Original Message----- From: cctech-bounces at classiccmp.org [mailto:cctech-bounces at classiccmp.org] On Behalf Of William Donzelli Sent: 18 October 2007 04:12 To: General Discussion: On-Topic and Off-Topic Posts Subject: Re: 4004 and IC history / was Re: Vintage computer photogallery > I'm sure I saw a development system at DEC for the 4004 running on a PDP-8 circa 1975. I think in its collection, RCS has a DEC Y187 card (the only yellow handled Flip Chip I have ever seen) that has a 4004 on it. -- Will

18 years, 8 months

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"Requiem for the Mainframe" on CBC-Radio, 4 PM Saturday

by hilpert＠cs.ubc.ca

Brief notification, but I just heard a blurb announcing as per the subject line, for those who happen to be near the radio in the next hour and can tune in the CBC (after the news at 4). (It's on the show "SPARK", if one wishes to try to hear a repeat.) It is about the mainframe computer, but that's all I got ... can't testify further as to the content.

18 years, 8 months

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Quick survey

by dm561＠torfree.net

Date: Sat, 15 Dec 2007 17:53:16 -0800 From: dwight elvey <dkelvey at hotmail.com> Subject: RE: Quick survey <snip> >Hi > There is nothing in the drive that is specific to the number >of sectors. ------- Except that a number of "modern" drives will not go ready and pass data with any hard sector disks. ------ > The following were 10 sector disk: >Polymorphic 8813 Used both single and double density disk >H8/89 H17 controller used single density >NorthStar single density ( double?? don't think so ) > These are all 5.25inch. As far as I know, 10 sectored was >the most common. I don't know of any that used 16 sectored >and never heard of 9 sectored. >Dwight -------- Just goes to show ya: all I've got are 16 sector disks, originally used in CBM computers (not because they were needed but because they were cheap) and now handy for my Vector Graphic MZs. I think Jerome was talking about 9 sector soft sector disks. mike

18 years, 8 months

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digital camera capabilities

by rdawson16＠hotmail.com

As an expert in this area, my opinion is that silicon sensors have a long ways to catch up to film. Both CCD and CMOS sensors lack in resolution and the spatial sampling artifacts Der Mouse mentioned are only part of the problem. (CFA array, metal shading of the cell) The world however, is focused (hahah pun intended) on the megapixel wars. Far more important is the geometry of the color filter array and conductors at the periphery, causing viginetting. Also, the conversion of the A/D in both systems is only 12 bits, far below the dynamic range of film and the eye. While at Micron, we developed a high dynamic range sensor for the security camera market, by varying the cell precharge and a sub ranging A/D for the sample. Imagine a security camera viewing a dark face in the lobby, and the security cam looking outside the front door glass at the daylight street too, we could image both of these simultaneously, no f stop changes... Lucas Film Pioneered the OpenEXR high dynamic range format: http://www.openexr.com/ Also take a look at where film is with the Gigapixel project: http://www.gigapxl.org/ Film has a few miles left for sure. Randy > From: mouse at rodents.montreal.qc.ca > Date: Sun, 16 Dec 2007 11:03:30 -0500 > To: cctalk at classiccmp.org > Subject: Re: digital camera capabilities / was Re: 1000+ old computer in > > > The effective resolution of 35mm film is IIRC considered by > > professionals to be in the 27MP range; DSLRs are rapidly approaching > > this. > > Perhaps - but film still has attributes which digital cameras don't, > such as lack of aliasing artifacts (because the grains are randomly > dispersed in the film instead of being in a neat rectlinear grid). > > /~\ The ASCII der Mouse > \ / Ribbon Campaign > X Against HTML mouse at rodents.montreal.qc.ca > / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B _________________________________________________________________ Don't get caught with egg on your face. Play Chicktionary! http://club.live.com/chicktionary.aspx?icid=chick_wlhmtextlink1_dec

18 years, 8 months

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Small SBC kits for Christmas!

by kerobaros＠gmail.com

So, every year I like to get myself a little something; this year, I'm probably going to be getting a new computer (outside the realms of this list), but I'd also like to get some kind of single-board kit that I can work on. I'd like something along the lines of a ZX-81 kit, although it looks like those are selling for somewhere around $250, when you can find one. SpareTimeGizmos' Elf 2000 kit also looks fantastic, but I don't have an 1802 or an 1861 to use in the thing, and I'd rather not hunt any down. (If anyone wants to get rid of theirs, though, let me know. *grin*) Has anyone seen any similar kits out there? They don't have to be useful for anything, just fun to play with, and not horribly difficult to put together. I can solder fairly well, and I'm mean with a multimeter, but I don't have the money for my own oscilloscope; I just use other peoples' when they're not looking. Thanks, folks! ~Matt

18 years, 8 months

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Quick survey

by cclist＠sydex.com

Would I be more-or-less correct if I assumed that the bulk of hard- sectored diskettes in use fell into two groups: 16-sector 5.25" and 32-sector 8"? I know that there are other physical formats, but I'm wondering if that would have 90% coverage? Thanks, Chuck

18 years, 8 months

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Homebrew Drum Computer

by roger.holmes＠microspot.co.uk

Your target of the technology of 1963 fits reasonably well with my 1962 mainframe, it uses drum(s) for backing storage (holding program and data overlays to be brought into core) but I don't think that makes much difference to the drum itself, other than you may want more than one read/write head per track. Each drum looks to be about a foot diameter and about a foot and a half long. They spin at 5240 rpm on a vertical axis. The drum is made of aluminium and the manufacturers (International Computers and Tabulators) had a lot of trouble getting the surface coating right, trying all sorts of high tech methods until they found the most effective method was for someone to smooth it on by hand while the drum was spun at low speed, rather like a potter throwing a clay pot. They also had problems with the length of the drum, and had to logically divide it into two sections, each one with its own timing track and datum track. Hopefully if you keep the drum length small this will not be a problem for you. The drums are powered by 3/4 horse three phase motors with V-belts providing a step UP in speed from just under 3000rpm at the motor to 5240rpm. They do not need clean room conditions, they are not sealed, and even have a fan to draw cold air up from the bottom over the surface and out the top, or is it the other way around, I can't remember, the fan are currently removed anyway and the drums run fine in a rural environment (i.e. reasonably clean air, no coal fire smoke/smog/ diesel particulates) The drum sits within an aluminium casing which holds 244 (+some spares) read/write heads arranged in a helix so they do not need to be physically close to each other. The heads do not fly, and can be moved in and out using an Allen key, which is apparently done whilst watching a pressure gauge on an airline blowing air through a venturi in the read/write head, so that when the air pressure reaches a certain level, the head must be close enough to the drum because the drum is starting to impede the air flow. The steel screws have now rusted and seized in the aluminium but work just fine because if can't work loose they can't go out of adjustment. The drum is coated rather than plated, I know this because when certain machines used by the Home Office for security purposes were decommissioned, a friend of mine was required to dismantle the drums and wash the magnetic coating off of the drums before they (the drums) were allowed to leave the premises. The machines had earlier survived being blown up by terrorists detonating a bomb on the window ledge outside one of the computer room windows. They don't make them like that any more, tough as old boots! The same friend also worked on a serial drum machine with valves which was installed at a Carbon factory where the inside of the machine used to get covered in conductive fine carbon dust. It is amazing it worked at all. Another friend worked on modern electronic weighing equipment at a phosphate factory using bird droppings as the raw material. He was called in to one machine which had stopped working the previous day, and found a small rubber grommet had failed, the chemicals had got in and eaten the resin of the PCBs and the copper tracking was hanging loose inside the cabinet, it seemed that it had somehow been working in that state for some time because it would have taken some weeks for the resin to be consumed, so maybe this contradicts my statement that they don't make them like that any more. The 1MHz main machine clock is derived from the 250KHz drum timing track, so no need to synchronise to the drum except when switching between drums, or the two halves of a drum. The machine can also be run from a separate clock, though of course all drum accesses fail. For fault finding, it can even be run one cycle for every time you press a button, wonderful to watch data shifting through the registers displayed on the front console and see where your data is getting corrupted. Not so good for fault finding the drum, magnetic tape or other peripherals though. I hope some small part of these details might be of help to you, good luck with the project.

18 years, 8 months

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KayPro II keyboard schematic?

by ajp166＠bellatlantic.net

> >Subject: Re: KayPro II keyboard schematic? > From: ard at p850ug1.demon.co.uk (Tony Duell) > Date: Sat, 15 Dec 2007 23:09:21 +0000 (GMT) > To: cctalk at classiccmp.org > >> It has an 8048 uP if memory serves and the output is TTL level serial >> ASCII. Making it put out parallel would be a major hackup including >> reprogramming an 8748. > >Or alternatively converting that serial output to parallel using an >external circuit. How hard that is depends on the format of the serial >data. If it's an asynchonous signal, with start and stop bits, a 40 pin >dumb UART chip should do it. > >What was used inside the Kaypro to receive the keyboard data? Z80 DART, The keyboard is a simple TTL level serial (async) protocal. It's bidirectional for lighting leds if memory serves. Allison > >-tony

18 years, 8 months

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Homebrew Drum Computer

by ajp166＠bellatlantic.net

> >Subject: Re: Homebrew Drum Computer > From: Gordon JC Pearce <gordonjcp at gjcp.net> > Date: Fri, 14 Dec 2007 10:01:09 +0000 > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > >On Thursday 13 December 2007 07:48:00 Robert Nansel wrote: > >> Certainly I could trash a few old cassette decks, or even get some >> floppy R/W heads to experiment with audio recording tape super-glued >> to a soda can, but I really want to get at least the performance the >> old machines could produce, so that means a reasonably fast drum RPM, >> somewhere around 6000 RPM, say. > >That's actually pretty fast, and anything you stick to the drum will need to >be stuck very firmly! By comparison, a washing machine in fast spin goes at >roughly a quarter of this speed, and a typical car engine is reaching >its "red line" at around 6000rpm... > >You would need an extremely good workshop to machine up a drum that would stay >in balance at this sort of speed. It's actually the sort of thing that you >might want to farm out to a specialist machine shop. I would be inclined to >make the drum out of a bit of thick-walled aluminium tubing, carefully bored >to remove any imperfections from the inside that might affect the balance. A >couple of aluminium end caps would take a thickish steel axle and the >bearings (which would be tricky in themselves - they'd need to be sealed to >prevent grease being thrown out, or something capable of running fairly dry >at high speed). Then you'd skim the drum to ensure it was perfectly >concentric - any runout would very quickly destroy the bearings at 6000rpm. >Some motors use little sealed ball races. I'd consider looking at teeny-tiny >taper roller bearings like car wheel bearings, so that you could use a shim >to set the preload very accurately to remove any play. I can probably >provide a scan of a car gearbox manual that shows *exactly* how to do this >bit. > >You'd probably need to balance it after painting or otherwise coating it with >some sort of magnetic material. I don't know what you'd use for that. You >could probably research what they used in early drives. I am now entering >the realms of speculation, but my gut feeling is that you'd need to somehow >spray it on and rub back the layers to get a perfectly smooth finish - when >it's done it shouldn't quite be hot-rod shiny but it should be very flat and >polished. > >Over to Tony, I think... Most of the old Drum machines spun at 1200, 1800, 3125 or maybe a screamigly fast 3600. Though 1800 is the more common. Also most used "fast tracks" that had more than one head per track radially so that a partial rotataion was needed. A good machine to study is the Minuteman Missle guidence computer. It was bit serial and used a disk as a "drum" rotating memory. Allison Allison >Gordon

18 years, 8 months

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Homebrew Drum Computer

by bnansel＠bigpond.net.au

I thought of this, too. So far I haven't found an online source of them (Google search terms: "glass delay line" OR "quartz delay line" OR "ultrasonic delay line" TV PAL OR NTSC). -Bobby Fri Dec 14 19:10 Tony Duell wrote: > I wonder if you could use those glass delay lines that were used in > PAL > colour TV receiver until fairly recently (and there must be plenty > still > around)? Alas they have a somewhat odd delay time (a little less than > 64us -- one line period of the European TV signal), but I am sure you

18 years, 8 months

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KayPro II keyboard schematic?

by robert.maxwell＠creationtech.com

Got a UART? It will make the Kaypro keyboard output into parallel without changing a thing. The signal's 300 baud RS-232 at TTL levels. Bob Maxwell

18 years, 8 months

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Homebrew Drum Computer

by dm561＠torfree.net

Date: Sat, 15 Dec 2007 13:23:13 +1030 From: Robert Nansel <bnansel at bigpond.net.au> Subject: Homebrew Drum Computer >I thought of this, too. So far I haven't found an online source of >them (Google search terms: "glass delay line" OR "quartz delay line" >OR "ultrasonic delay line" TV PAL OR NTSC). >-Bobby Fri Dec 14 19:10 Tony Duell wrote: >> I wonder if you could use those glass delay lines that were used in >> PAL colour TV receiver until fairly recently (and there must be plenty >> still around)? Alas they have a somewhat odd delay time (a little less >> than 64us -- one line period of the European TV signal), but I am sure ----------------------- I've got some old VCR boards with 2 glass delay lines on 'em: Markings: DL BTB85B 042 (Component # DL2K0, 6cm long, 4 pins) And: ADL-FN2038M 337P16301 4003 (DL6A0, 3cm, 3 pins) Just slabs of quartz with wires attached (the covers are removeable). Might be tricky to find specs though; unfortunately no idea of the VCR make/model. Also should have an old MS delay line somewhere. mike

18 years, 8 months

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Homebrew Drum Computer architecture

by cclist＠sydex.com

On 15 Dec 2007 at Robert Nansel <bnansel at bigpond.net.au>: > * Delay lines: I have a junk magnetostrictive DL on the way. I > don't know if it works. Golly, if you're talking about producing your own drum, a magnetostrictive delay line would seem to be like a walk in the park. Find some nickel wire; make a large-looped coil with the turns supported by something like neoprene spacers so that they're mechanically isolated; put a coil on each end. Shock-mount the whole affair in a box. The Packard-Bell 250 was a great little machine along the lines that you're contemplating. Used delay-line memory and had a 22-bit word. You could plug it into a 115-volt wall outlet. Few transistors and lots of diodes, IIRC. Really one of the earliest minicomputers around. There are several that are extant. I recall seeing the memory in a 250 and being surprised at its simplicity. > I was thinking I would implement a data stack and a return stack, > each being made of short recirculating buffers to hold the top two or > three stack entries, with the older entries swapped to longer buffers > with corresponding longer access times. Allowing for the overall > insanity level of this project, is this seem a sane strategy? Sounds pretty complicated to me. Why not a simple one-plus-one architecture? It may not be fast, but then, no drum- or delay-line- based machine is going to be a speed demon... Cheers, Chuck

18 years, 8 months

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Quick survey

by andrew-lynch＠sbcglobal.net

Would I be more-or-less correct if I assumed that the bulk of hard- sectored diskettes in use fell into two groups: 16-sector 5.25" and 32-sector 8"? I know that there are other physical formats, but I'm wondering if that would have 90% coverage? Thanks, Chuck -----REPLY----- Chuck, If I were to pick two of the most common, I would pick 10 sector 5.25" hard sector floppy disks and the 32 sector 8" hard sector floppy disks. There is a less common 16 sector 5.25" hard sector floppy disk as well used on Vector Graphic, AES, Exidy Sorceror, and a few other exotic platforms. Of course, none of the hard sector media are exactly common... [drifting slightly off thread but in a related manner] BTW, I did get Catweasel Vector Graphic working. I am in testing now and will be changing the output format to support the simulator work underway presently. Nothing major; just time consuming and the usual stuff. My Catweasel programs seem to work fine but are not really designed for easy modification. Quick hacks rarely are. It turns out to be major oversight though; there are even more diverse and incompatible disk formats for VG than for NorthStar or Heath which is really saying something. The frakkin' hard sector disk formats are just crazy in the ways things vary >from one vendor to the next and even within different OS's from the same vendor. "No rules for hard sector disks" is a profound understatement! Thanks! Andrew Lynch

18 years, 8 months

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test

by jules.richardson99＠gmail.com

Apologies for noise!

18 years, 8 months

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Small SBC kits for Christmas!

by evan＠snarc.net

Apple I is Vince's deal -- www. brielcomputing.com (or maybe it is "brielcomputers.com" or something like that...) -----Original Message----- From: "Matt Lichtenberg" <kerobaros at gmail.com> Subj: Small SBC kits for Christmas! Date: Sat Dec 15, 2007 9:23 am Size: 918 bytes To: cctalk at classiccmp.org So, every year I like to get myself a little something; this year, I'm probably going to be getting a new computer (outside the realms of this list), but I'd also like to get some kind of single-board kit that I can work on. I'd like something along the lines of a ZX-81 kit, although it looks like those are selling for somewhere around $250, when you can find one. SpareTimeGizmos' Elf 2000 kit also looks fantastic, but I don't have an 1802 or an 1861 to use in the thing, and I'd rather not hunt any down. (If anyone wants to get rid of theirs, though, let me know. *grin*) Has anyone seen any similar kits out there? They don't have to be useful for anything, just fun to play with, and not horribly difficult to put together. I can solder fairly well, and I'm mean with a multimeter, but I don't have the money for my own oscilloscope; I just use other peoples' when they're not looking. Thanks, folks! ~Matt

18 years, 8 months

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Homebrew Drum Computer (magnetic heads)

by mike＠brickfieldspark.org

The SDS9300 I used to service had a drum memory, unfortunatley can't remember the type but I do recall that the drum was slightly tapered and had a rising bearing assembly. As the drum finally ran up to speed it rose an amount to bring the heads to the correct position and gap. Basically a "parking" system, when stopped the drum had dropped, so the heads were not at their working position. Heads were adjusted for position with the drum stopped using gauges, so as it was stopped and down you did not risk damaging the track. Spin it up to speed and the heads automatically got to the tracks and flying height. I recall it being about 2ft in diameter and about 4ft tall took about 30 seconds to come to speed and had its own motor generator set as it ran on a dedicated 60 cycle supply not the usual 50 we have here in the UK. I think it had 4 banks of 24 heads in fixed position. It was the one bit of kit we did not touch, a specialist used to fly in from the US once a year to check it and rewrite the timing tracks. Mike

18 years, 8 months

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Al Kossow, here are the versaplot sources

by rdawson16＠hotmail.com

Al, A while back you asked for the Versaplot sources, I have them here with a port to the PC DOS (Ryan-Mcfarland Fortran). I also found them on the web: http://history.dcs.ed.ac.uk/archive/apps/edwin/randomvms/ A google of versaplot turned this up, and also some manuals in what looks like troff format. It looks like all the DECUS stuff is out there itoo f you google a bit. I would like to see your MOVIE.BYU! Randy _________________________________________________________________ i?m is proud to present Cause Effect, a series about real people making a difference. http://im.live.com/Messenger/IM/MTV/?source=text_Cause_Effect

18 years, 8 months

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cctalk Digest, Vol 52, Issue 30

by cclist＠sydex.com

Date: Fri, 14 Dec 2007 14:52:29 -0800 From: "Rick Bensene" <rickb at bensene.com> > Some of the smaller drum-based computers from the late '50's and earlu > '60's (transistorized) had drums that didn't rotate nearly as fast as > 6000 RPM. I don't know--the drum on the IBM 650 spun at 12,500 RPM, was 4 inches in diameter and about a foot long. This is not a project I'd launch into lightly. In the 70's and 80's Meshna would occasionally offer a mil-surplus drum unit for sale usually from some some airborne installation (i.e. used in radar). Lots of heads and no guarantee. The precision necessary in the mechanicals is pretty daunting. The heads fly at a few micrometers above the surface of the drum, which pretty much mandates some sort of clean-room environment. The bearings would need close to zero runout and getting the surface of the drum coated smoothly enough, either by plating or with a magnetic emulsion would also be an obstacle. If you have a good precision machine shop and mechanical engineering skills at your disposal, you could try it. Personally, I'd rather work something up with a magnetostrictive delay line memory--easier to build and quite robust--and just as "vintage". I recall that even in the 70's, drums had their problems. On the CDC STAR, every so often, a station would go down because of a "drum error"--more frequently than the disk drives encountered errors. You could make the heads on a Univac Fastrand II drum "ping" just by jumping up and down on the floor near the monster. I also recall that the ADL folks at CDC were working on a "super drum"--a very high speed unit that spun in a vacuum(IIRC) to be used as a paging store for the STAR. I recall the Neil Lincoln mentioned that the time between the observation window being clear and coated with drum surface was typically a few minutes at best. There's a nice story about the Manchester Mark I drum here: http://www.computer50.org/mark1/gethomas/manchester_drums.html About the only item of the correct size and tolerances that's readily available today, it seems to me, would be the drum unit out of a laser printer or copier. I don't know if the OPC layer could be easily stripped off and replaced with oxide, but it might be worth a try. If you're really serious abou this, I'd be willing to donate a head >from a CDC 808 disk unit--4 bit parallel recording. Cheers, Chuck

18 years, 8 months

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KayPro II keyboard schematic?

by dm561＠torfree.net

Date: Thu, 13 Dec 2007 21:55:51 -0500 From: "Andrew Lynch" <lynchaj at yahoo.com> Subject: KayPro II keyboard schematic? >Hi, >I recently bought a KayPro II keyboard. It contains a nice Keytronics >mechanical keyboard and really nice case. I'd like to convert it to a >parallel ASCII keyboard or just reuse its case but was wondering if anyone >had the schematics? >Please let me know if you have the KapPro II keyboard schematics. Thanks! >Andrew Lynch ------------- How about leaving the keyboard intact and just adding a simple serial>parallel converter between it and the VG box? Add an EPROM for code conversion if necessary. I've got some serial interface cards for Olivetti typewriters (with schematics) that you could probably hack fairly easily if you didn't want to start from scratch; even FIFO buffers for typeahead, although you wouldn't need that with a Vector. mike

18 years, 8 months

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Homebrew Drum Computer

by ajp166＠bellatlantic.net

> >Subject: Re: Homebrew Drum Computer > From: Gordon JC Pearce <gordonjcp at gjcp.net> > Date: Fri, 14 Dec 2007 14:42:34 +0000 > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > >On Friday 14 December 2007 14:19:06 Jules Richardson wrote: > >> Very interesting project. Won't standard tape heads only work reliably if >> the magnetic material's passing by at quite a narrow range of speeds, >> though? Google suggests that's 1 7/8" per second, which isn't very fast at >> all - a drum that can do a few tens of RPM seems possible, but 6000?? > >I don't think it makes a difference. The higher the speed, the larger the >voltage from the flux transition, but that shouldn't be a problem (within >reason). The head gap and medium speed dictates the "resolution" of the >system. You can think of it as being like trying to write with different >sizes of pen nib. > >Look at reel-to-reel audio recorders - they may run at a variety of speeds, >giving a tradeoff between audio quality and recording time. You can use a >higher flux density with a larger head gap (and a correspondingly larger >drive signal), but you need to haul the tape through faster to maintain the >bandwidth. However the inductance of the head windings are a significant factor in how high you can go for bandwidth. >On playback, you get the problem that higher frequencies produce a higher >voltage, hence the need for equalisation (not unlike the RIAA curve for >magnetic record pickups). > >In this case you probably just want to detect the presence or absence (or >possibly polarity) of a pulse. Equalisation won't be a worry. At low bit densities it's not an issue otherwise you get into peak shift. Low being around 300FCPI (Flux Changes Per Inch) based on testing I did 30 years ago. I was using the best ferrite heads I could get my hands on >from top of the line analog casette decks. Those heads were very limited and heads from 1/4" machines performed far better and still limited me to under 600FCPI at 15ips (~4800 bits sec) for NRZI and I could hit 9.6k using phase encoding. Most audio heads are not so hot for saturation work. Allison >Gordon

18 years, 8 months

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Homebrew Drum Computer

by ajp166＠bellatlantic.net

> >Subject: Re: Homebrew Drum Computer > From: Jules Richardson <julesrichardsonuk at yahoo.co.uk> > Date: Fri, 14 Dec 2007 08:19:06 -0600 > To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> > >Robert Nansel wrote: >> Certainly I could trash a few old cassette decks, or even get some >> floppy R/W heads to experiment with audio recording tape super-glued to >> a soda can, but I really want to get at least the performance the old >> machines could produce, so that means a reasonably fast drum RPM, >> somewhere around 6000 RPM, say. > >Very interesting project. Won't standard tape heads only work reliably if the >magnetic material's passing by at quite a narrow range of speeds, though? >Google suggests that's 1 7/8" per second, which isn't very fast at all - a >drum that can do a few tens of RPM seems possible, but 6000?? Correct, there is a relationship between gap width and media speed. I've used casette heads to 10ips but above that there are problems. one is the total inductance of the winding limit the upper frequency reponse (used as saturation recording head) to around 40khz and thats pushing it. Allison > >If I've got my numbers right, a small 6" drum has a diameter of approx 19" and >at 6000rpm will take 1/100 seconds to do a single revolution. That's 1900" per >second past each head - roughly 1000 times the typical operating speed of a >cassette deck. > >Build several low-speed soda can drums - equivalent in number to the word >length of your machine, then read/write data in parallel... (OK, that's a >humourous suggestion, but it wouldn't surprise me if someone hasn't tried it) > >cheers > >Jules

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[personal] cctalk Digest, Vol 52, Issue 27

by mike＠brickfieldspark.org

> My main component storage is a set of interlocking drawers arranged in a > block about 4 feet wide by 3 high. Some drawers are square-fronted > (about 1.5" sq) and some are double-width. The resistors are in > double-width drawers, with two E12 values per drawer. First row is > 10/12 ohm, 15/18 ohm, 22/27, 33/39, 47/56, 68/82. Next is 100/120, etc, > then 1k0/1k2, etc, and so on up to 680k/820k, then the last row is > assorted "1M to 8M2", "10M and over", "less than 10R", "high wattage", > and things like that. For E24 and closer-tolerance values, I just put > them in the drawer that's got the nearest-matching label. Capacitors I > have squeezed into 1 row, one decade to a drawer, and a couple of bigger > drawers for larger electrolytics. The really big ones are in a box > elsewhere. So spookily similar I'm now very very worried ! or perhaps its a British thing. > To give an example of how the ICs are stored, there's a drawer for "LS00 - > LS80" or thereabouts, with the lower end of that range stored in the > front and the upper half in the rear section of the drawer. So there > are 4 or 5 drawers for each logic family. Two places I used to work had > one drawer per type but that's overkill for my collection. One drawer for 2-4 types for Ic's Transistors diodes. Mike

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Subject: Semi-OT:Storing electronic parts

by mike＠brickfieldspark.org

> Message: 6 > Date: Thu, 13 Dec 2007 06:12:19 -0800 (PST) > From: Mr Ian Primus <ian_primus at yahoo.com> > So, now I think I need to actually, finally organize my parts. You see, I > started to do this a long time > ago, and I have a lot of those little plastic drawers. I got about as far > as the basic parts, and half way > through the electrolytics. Everything else is semi-sorted into drawers, > albiet with rather vauge I set up some of those drawers years ago (more than 25, eek) resistors and caps sorted by value, Ics transistors diodes by type #. I was in small scale production and the system seemed to work well enough. Untill recently I had a couple of regular products for customers who shipped in parts so they had a set of drawers for themselves and a very basic stock control system on an Excel spreadsheet. No longer in production but still have the drawers, a pain to set up but many years ago, but I can find most things I want in seconds. > Otherwise, you'll spend two hours just trying to find that 330 ohm current > limiting resistor you need. Thats why I set it up. > about - how bad is it to store IC's in those clear plastic parts drawers? > Any problem with static? > What about CMOS chips? A lot of my personal stuff is older 74 flavours, that does not seem to suffer static problems, Cmos is kept in antistatic foam or those black a/s carriers that the I/c's are shipped in. I have a whole box full of empty carriers if somebody wants them. I'cs shipped in A/s tubes are kept in tube untill used. The system has served me well over the years, a bit anal maybe but it worked for me. Mike

18 years, 8 months

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SEBHC has moved to Google groups

by jack.rubin＠ameritech.net

SEBHC - the Society of Eight-Bit Heath Computerists - has become a Google group. If you are interested in the H8, the H89, the better half of the H/Z100, or the ETxx trainers, please come join us. We maintain an extensive archive of Heath 8-bit software, both HDOS and CP/M, as well as a large collection of hardware and software documentation. This is a great group which includes several ex-Heath employees as well as others deeply versed in the workings of these computers. The group is closed in the interests of sanity and to protect the archive; if you're interested come to http://groups.google.com/group/sebhc?lnk=gschg and request membership. Jack No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.503 / Virus Database: 269.16.9/1155 - Release Date: 11/27/2007 8:30 PM

18 years, 8 months

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SGI drive sleds and interfaces?

by g-wright＠att.net

-------------- Original message ---------------------- From: Richard <legalize at xmission.com> > > OK, with my new Origin 2000 machines, I was thinking that I could use > these SGI drives+sleds that I had purchased previously, where the > seller said they would work in Onyx2/Origin machines. However, while > the sleds appear compatible, the drive interface is not. > > Is there any online guide that compares the different drive sled > designs for SGI machines so that I can compare what's being offered on > ebay to identify the machines that can use it? > > For instance, my drives have a high density connector that is only > about 1" long, but the Origin 2000 has a high density connector that > looks to be about 2-2.5" long. > > Is my only recourse to scrape through individual manuals to try and > find diagrams? > -- > "The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download > <http://www.xmission.com/~legalize/book/download/index.html> > > Legalize Adulthood! <http://blogs.xmission.com/legalize/> Hi Richard The ones I have seen take standars SCA drives ???? Power and data in the same connector ??? The Connector is a little more rugged looking. same as a Later Sun. - Jerry

18 years, 8 months

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KayPro II keyboard schematic?

by lynchaj＠yahoo.com

Hi, I recently bought a KayPro II keyboard. It contains a nice Keytronics mechanical keyboard and really nice case. I'd like to convert it to a parallel ASCII keyboard or just reuse its case but was wondering if anyone had the schematics? Please let me know if you have the KapPro II keyboard schematics. Thanks! Andrew Lynch

18 years, 8 months

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[lisaem] LisaEm 1.2.0 - No ROMs? No problem!

by ray＠arachelian.com

LisaEm 1.2.0 is available for download right now, from the usual place: http://lisaem.sunder.net/downloads.html Many LisaEm users have complained that ROMs are too difficult to extract. The new version of LisaEm solves this by allowing you to run with out a ROM. If you wanted to try LisaEm, but couldn't because you didn't have ROMs for it, now you can! It emulates the functions of the Lisa Boot ROM as well as the Dual Parallel Card without requiring a ROM, and allows you to boot into Lisa Office System. If you've felt limited by only having a single emulated Profile hard drive because you didn't have the Dual Parallel ROM, the new version also emulates these, without requiring a ROM. All you need is Lisa Office System and LisaEm. As this is the first release of this feature, don't be surprised if you encounter bugs. Please report any unexpected behavior so that I can fix it. :-) Additionally, I've added two movies that show how to install Lisa Office System and MacWorks. (MacWorks still doesn't work properly on LisaEm however.) ------------------------------------------------------------------------------ Lisa Emulator Change History http://lisaem.sunder.net/ ------------------------------------------------------------------------------ 2007.09.19 - fixed romless floppy boot to always boot from floppy and not switch to Profile. 2007.09.15 - debugging ROMless boot. new bug: when trying to boot from floppy, if a profile exists and is bootable, LOS starts up from the Profile instead of the floppy. 2007.09.09 - David Cecchin's XPM icon in unix 2007.09.07 - added Save/Load PRAM to Preferences - Quit now closes any open Preference window as well 2007.08.29 - libdc42 macbinii encoded dart to dc42 conversion bugfix 2007.08.16 - added LOS error codes to ROMless error handler - fix raw screenshot crash 2007.08.13 - got both ROMless boot and ROMless dual parallel card to work 2007.08.06 - individual profile power controls + create new profile inside a new menu named profile. 2007.07.28 - replaced all exit() and EXIT() calls with messages before quitting emulator so at least we know what crashed. 2007.07.27 - ROMless works with both profile and floppy now. - Fixed a bug with configuration saving. 2007.07.26 - Tracelog checkmark correction 2007.07.25 - added Zap PRAM button in main Preferences panel 2007.07.23 - ROMLess booting - floppy works 2007.07.19 - ROMLess booting start 2007.07.12 - RESET opcode supervisor mode bug fix. 2007.07.10 - CPU core tests If you'd like to support this project, you can do so by sending me something from my Amazon wish list. (Used books and DVD's are perfectly fine with me.) The trains are for my kid. :) http://www.amazon.com/gp/registry/wishlist/14EOBF86ARMDT/ref=wl_web/

18 years, 8 months

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Semi-OT:Storing electronic parts

by ian_primus＠yahoo.com

Well, I've made lots of progress on the eternal task of cleaning, sorting and organizing. I can now see my entire workbench! I found half a dozen #2 Phillips screwdrivers I hadn't seen in a while, and while vacuuming, I probably picked up a couple pounds of screws, wire insulation bits and solder drops. So, now I think I need to actually, finally organize my parts. You see, I started to do this a long time ago, and I have a lot of those little plastic drawers. I got about as far as the basic parts, and half way through the electrolytics. Everything else is semi-sorted into drawers, albiet with rather vauge categories "Transistors... Diodes..." or completely unsorted (Salsa jars, butter tubs, shoe boxes, coffee cans and Altoids tins). So now, I need to sit down, for a good long day, and sort parts into drawers. And herein lies my question - how do you manage a large parts collection? I mean, the phrase "junkbox" generally referrs to a somewhat organized system of finding parts, not just a copier paper box full of parts. Otherwise, you'll spend two hours just trying to find that 330 ohm current limiting resistor you need. So - how do other electronic hobbyists sort parts? How far do you organize them? A drawer for each value of resistor? Drawer for a range of values? What works well, to minimize the time spend searching for components? Also, another thing I have been wondering about - how bad is it to store IC's in those clear plastic parts drawers? Any problem with static? I've never noticed any, but then again, so far I've only got a handfull of basic TTL logic sorted out. The rest are still in tubes and boxes. What about CMOS chips? So, I'd be interested to hear what other people have to say on the subject - and Jay, I hope this is on-topic enough. I mean, these are all parts used for repairing and maintaining on-topic hardware, so I think it counts. All of us that fix this stuff need to keep track of parts. The next time I need a 1488 to repair a terminal that won't transmit, I don't want to spend four hours trying to find it. -Ian

18 years, 8 months

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Semi-OT:Storing electronic parts

by dm561＠torfree.net

------------Original Message: Date: Thu, 13 Dec 2007 06:12:19 -0800 (PST) From: Mr Ian Primus <ian_primus at yahoo.com> Subject: Semi-OT:Storing electronic parts Well, I've made lots of progress on the eternal task of cleaning, sorting and organizing. I can now see my entire workbench! I found half a dozen #2 Phillips screwdrivers I hadn't seen in a while, and while vacuuming, I probably picked up a couple pounds of screws, wire insulation bits and solder drops. So, now I think I need to actually, finally organize my parts. You see, I started to do this a long time ago, and I have a lot of those little plastic drawers. I got about as far as the basic parts, and half way through the electrolytics. Everything else is semi-sorted into drawers, albiet with rather vauge categories "Transistors... Diodes..." or completely unsorted (Salsa jars, butter tubs, shoe boxes, coffee cans and Altoids tins). So now, I need to sit down, for a good long day, and sort parts into drawers. And herein lies my question - how do you manage a large parts collection? I mean, the phrase "junkbox" generally referrs to a somewhat organized system of finding parts, not just a copier paper box full of parts. Otherwise, you'll spend two hours just trying to find that 330 ohm current limiting resistor you need. -Ian ------------Reply: Boy, does that sound familiar! For resistors, I was lucky enough to have a lot of small plastic boxes that Sprague used to put their caps into; they're stacked up in a couple of small partitioned cardboard parts bins. Things like tantalum caps, fuses, hardware etc. I keep in those small partitioned clear plastic craft boxes. Diodes and small transistors are in individual small paper bag/envelopes, which in turn are in small cardboard boxes, file folder style. You could use the same for resistors & caps. Bigger parts go into the same partitioned cardboard parts bins use for the resistor boxes. ICs I keep loose in drawers, unless I have a lot of one type which I keep in tubes; a few special MOS ones I kept in foam, but have had a few go bad with pin rot from a certain type of foam. Just keep the humidity reasonable. The problem with semi-inflexible systems like drawers is adding new items; I finally started a spreadsheet cross-referencing IC numbers to drawer/compartment so I don't have to worry about keeping them in any sequence and can also double up, and it also gives me an idea of what I've got (as long as I remember to keep it current ;-) mike

18 years, 8 months

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Symbolics XL400/1200

by davis＠saw.net

The machine is available in Portland Or or preferably, up the gorge in Goldendale Wa. which is located about 100 miles east of Portland. The machine could be shipped, but it would require a pallet for the case, foam for the monitor and separate packing for the drive and boards. I'm not sure how much it's worth. I have had an offer for $370. So I guess thats a start. The system includes the mono hi-res graphics monitor, space cadet keyboard, full document (user) set, but no hardware prints (sorry) and a frame tosser board. I'll throw in a couple bus mice, but they will need to be rewired. I'll fire it up and verify that it still boots. (it did 6 months ago) If you pick it up in goldendale, I'll let you dig around in my shed for other goodies. The machine is badged as a XL400 but boot reports a XL1200. I assume it's the extra memory and possibly software upgrades. It has been stored inside, in a clean dry environment since I picked it up about 7 years ago. Jim Davis.

18 years, 8 months

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Mike Quinn Electronics -- one last chance

by brian＠quarterbyte.com

Hi Folks, As many of you know, the venerable Mike Quinn Electronics in San Leandro, CA (down by the Oakland Airport) closed last Saturday with virtually no advance notice. If you're in the San Francisco Bay Area, you know Mike Quinn is the one of the very last of the nitty gritty electronics salvage shops left, with an emphasis on gritty. I stopped by today, and mentioned to Maurice, the owner, that a lot of people would have liked to have had one last shot at a visit. So, he has extented an invitation to y'all to visit next week, Tuesday through Friday February 7-10, 2006, during normal business hours, for one last shopping spree. He is trying to find a buyer for the stock in the store. This is almost certainly the last chance to visit. If you can, it's worth doing whatever you have to do to make the pilgrimage. Buy some stuff to thank Maurice for keeping it going all this time. There are zillions of connectors and components, heaps of transformers and power supplies, scads of cables and keyboards and monitors and other PC junk, a jet fighter console or two, a couple of early 80's HP desktop computers (the ones with built-in BASIC, can't recall the model numbers), lots of relays, and much more, all arranged in an archaeologically interesting and un-seismically-safe way. If you need it, they have it, and they might even be able to find it. Mike Quinn Electronics 401 McCormick Street (at the corner of Adams and McCormick) San Leandro, CA 94577 Brian

18 years, 8 months

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TRADIC

by evan＠snarc.net

A few days ago, someone asked about TRADIC. Tonight I stumbled upon a mention of this computer on page 204 of the book "Crystal Fire" (Michael Riordan and Lillian Hoddeson, 1997). The authors wrote, "In January 1954 Whippany engineers built a fully transistorized computer for the Air Force. Called TRADIC (for TRAnsistorized DIgital Computer), it used 700 point-contact transistors and more than 10,000 germanium crystal rectifiers in its circuits. Capable of performing a million logical operations every second, TRADIC was the first completely solid-state computer; it approached the speed of computers based on vacuum tubes." By "Whippany" they meant the Whippany, N.J. location of Bell Labs.

18 years, 8 months

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QIC drives need a home!

by jeffj＠panix.com

I'm cleaning off my workbench and don't need this paperweight: Archive 5945L-3 QIC drive with daughter-board. It's a 60 mb drive but the card had no useful numbers. I suspect it's a QIC-02 to QIC-36 adapter. If anyone's still using such things, let me know, it's available! Jeff Jonas jeffj at panix.com

18 years, 8 months

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free SGI Origin 2000

by ingrammp＠earthlink.net

Well, they may not be exactly "classic" but they were interesting machines in their time... I have two (2) SGI Origin 2000 systems.... It's an 8 node, 195Mhz R10000, 512Mbyte, CD, 4Gbyte disk.. Has two HVD (high voltage differential as opposed to the current LVD ).. interfaces on each... and a PCI card adapter.. and a bunch of cables for connecting external disks and whatnot. Both are free for the taking and are located in Tucson..., and both were working when last turned off... stored in an air-conditioned corporate office. I'll help you load one or both onto your truck !! Mike

18 years, 8 months

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12" CRT for cost of shipping

by frustum＠pacbell.net

I listed a CRT on ebay and received no bids. If anybody in the US would like to pay for shipping, you can have it. I was told it was a replacement CRT for a TRS-80 (model 3 or 4, I guess) >from the guy who gave it to me. It is unused and thus has no burn in. Search ebay for auction #120193025277. Or you can view a greater variety of full scale images here: http://home.pacbell.net/frustum/ebay/tube/ Even if you don't have a trs-80 with a dead tube, perhaps you can turn it into a cool large screen vectrex instead.

18 years, 8 months

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Apple external SCSI drives

by colin.jensen＠gulfair.com

Good Morning Mark Have you had any luck or info on the Ricoh RH5500 drive. Thanks Colin Official Airline and Sponsor of the Gulf Air Bahrain Grand Prix 2008 www.gulfair.com ================================================================================================================= This is an e-mail from Gulf Air Co. It is privileged and confidential and is intended only for the individual or entity named above and contains information that is or may be confidential, non-public or legally privileged. Any retention, dissemination or distribution of this message other than to its intended recipient is strictly prohibited. If you have received this message in error, kindly reply back to the sender immediately and delete the original message and all its copies. =================================================================================================================

18 years, 8 months

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any one have Mini-Micro Systems magazines & digests?

by g-wright＠att.net

-------------- Original message from "Paxton Hoag" <innfoclassics at gmail.com>: -------------- > One of my favorite reference magazines was Mini-Micro Systems which > published from 1976 to 1989 by the Cahners Publications. They printed > 10 issues a year along with a Spring and Fall Peripherals Digest. I > think Starting in June 1984 they printed a Mini-Micro computers > special issue. > > I have one copy left, the 1983 Fall Peripherals digest. It is what I > was looking for when Jerry was trying to identify the CDC/QD drive he > had. > > Unfortunately the model numbers and what is printed on the drive don't > correspond (and from what I remember never did) > Hi, Paxton well you might be right on that. I have looked high and low and seem to keep coming up with different numbers for the drives. Here is what is listed on Mfaris site. for CDC and MPI (both names are on the label). http://www.mfarris.com/floppy/mpi.html http://www.mfarris.com/floppy/cdc.html - jerry

18 years, 8 months

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Some old ad pins

by silent700＠gmail.com

A while back a friend gave me a big tub of pins his father was going to toss out. His dad did sales and marketing for Zenith, I believe, and had these pins from a CES show in the early 80s. I've laid them all out and taken some pics: http://flickr.com/photos/chiclassiccomp/sets/72157603430282899/ There are many recognizable names in there, some rare ones (Esprit!) and some I have no idea what they are. Flickr users who can name some of the oddballs feel free to add Flickr notes to the pics to ID them. You'll probably want to view the pics full size, or at least larger than they display by default. j -- silent700.blogspot.com Retrocomputing and collecting in the Chicago area: http://chiclassiccomp.org

18 years, 8 months

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any one have Mini-Micro Systems magazines & digests?

by innfoclassics＠gmail.com

One of my favorite reference magazines was Mini-Micro Systems which published from 1976 to 1989 by the Cahners Publications. They printed 10 issues a year along with a Spring and Fall Peripherals Digest. I think Starting in June 1984 they printed a Mini-Micro computers special issue. I have one copy left, the 1983 Fall Peripherals digest. It is what I was looking for when Jerry was trying to identify the CDC/QD drive he had. Unfortunately the model numbers and what is printed on the drive don't correspond (and from what I remember never did) They have sections on drives, in fact they have separate sections listing 8", 5 1/4" and Micro Drives. The 5 1/4 " drive listing has 39 makers of internal and external 5 1/4" drives, including simple specs; sides, capacity, tracks, TPI, access time, transfer rate, dimensions and model numbers. Similarly for hard drives of all sizes (14" to 3") and removable cart drives. They also had a great reference section on Terminals and Printers. They are great reference magazines for collectors or for just identifying equipment. The collection is one of the things I miss the most, losing them in a house fire. Doing an Internet search I discovered WorldCat.org which indicates there is a Microfiche set at Oregon State University in Corvallis. I will have to go look. So does anyone have a set or the Microfiche? I think anyone who has a museum should think of looking for this magazine, especially the product digests for reference. -- Paxton Hoag Astoria, OR USA

18 years, 8 months

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list is open

by jwest＠classiccmp.org

List is back open for traffic. Let's try to keep it more on-topic please. Jay

18 years, 8 months

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Hazeltine 1200

by ajp166＠bellatlantic.net

> >Subject: Re: Hazeltine 1200 > From: Dave McGuire <mcguire at neurotica.com> > Date: Fri, 07 Dec 2007 00:54:03 -0500 > To: "General Discussion: On-Topic Posts Only" <cctech at classiccmp.org> > >On Dec 6, 2007, at 4:22 PM, Tony Duell wrote: >>> I'm also curious about what processor it's built around, if you >>> don't mind checking. >> >> Why does it have to have a processor at all? A number of the older >> terminals, both 'glass TTYs' and those with some limited control code >> response, like cursor positioning, were built from simple TTL (etc) >> chips. Sometimes the artchitecture was something like a processor (DEC >> VT5x, for example), sometimes it was just random logic. > > Of course it doesn't *need* to have a processor in the traditional >sense...I was just assuming that it would, as I was guessing it wasn't >much older than 1420 I had years ago. I could certainly be wrong. It's much older than 14xx maybe at least two generations. Actually the 14xx series was near the end of the line for Hazeltine designs and I remember being then for it in mid 78. By then they almost had the 15xx series working in production. Allison > -Dave > >-- >Dave McGuire >Port Charlotte, FL

18 years, 8 months

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CDC 5 1/4 floppy 77711501 / 77711800 specs, update

by g-wright＠att.net

-------------- Original message from "Chuck Guzis" <cclist at sydex.com>: -------------- > Well, I can tell you that MPI made 100 tpi FH drives--I have two of > them on my shelf here, date codes are 81-82. Unfortunately, the > labels have dried up and dropped off, so I no longer have any idea of > what their part number is. I've also got a couple in another > machine, but it's a bear to get at them. > > Does the drive have a little "daughterboard" plugged into the main > PCB with a 74ls123 on it? That'd be the "Drive Ready' circuit. I > don't know if all MPI 100 tpi drives had this though. > > "Micropolis" type 100tpi drives also have a slightly different pinout > than normal "Shugart" type drives (this includes the Tandon TM-100- > 4M). A big difference is that READY is pin 6, not 34. Maybe that's > what's causing your drive error. > > Just guessing... > > Cheers, > Chuck > Hi, Well Chuck and Paxton where right there. I took a chance and pulled a Quad denisity drive out of a Motorola system I got from Paxon (sorry Tony. I see your post) and all is well. It took 16 disks to back up close to 10 megs. I had to bulk erase the disks (DSDD) for them to work with either drive. Anadisk finds 80 cylinders and is able to read the whole floppy with out errors ( using a 1.2HD drive.) I have not workd with Image disk yet. I'm still out in the dark on the OS and how to make a bootable floppy. I cant get past there Menu system It seems to run on or with some type of basic. Below is a Boot screen for those with interest. The System is a small desk top 6 serial port business system. Thanks, Jerry ...................................................... <I-TIMERS><I-USARTS><I-PIC'S ><I-DMA'S > BOOTSTRAP LOADER VER 120A 31MAR83 S/N:000794 <I-TIMERS><I-USARTS><I-PIC'S ><I-DMA'S > <I-FLOPPY><I-MEM&CH><MEM DATA><MEM BANK> <MEM ADDR><HD SETUP><HD READI><VFY INCP> <HD READL><VFY LOAD> STARDOS SYSTEM UTILITIES REV 242B 10JAN84 STARDOS BASIC LOADER 1) ENTER MASTER MENU 2) ENTER SYSTEM UTILITIES MENU ENTER YOUR CHOICE 2 ########################################### # STARDOS SYSTEM UTILITIES - VERSION 242B # ########################################### 1) ENTER MASTER MENU 2) INITIALIZE DEVICE 3) COPY DISKETTE 4) COPY STARDOS 5) RECONFIGURE 6) BINARY BACKUP HARD DISK 7) BINARY RESTORE HARD DISK 8) INITIALIZE FILE SAVE DISKETTE 9) HARDWARE CONFIGURATION ENTER YOUR CHOICE 1 *** S T A R D O S II *** BASIC RELEASE 10.7 REV C 05JUN84 snip.................................................

18 years, 8 months

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ROM image for NEC PC-8300

by dm561＠torfree.net

-----------Original Message: Date: Mon, 03 Dec 2007 16:32:18 -0800 From: Josh Dersch <derschjo at msu.edu> Subject: ROM image for NEC PC-8300 Anyone out there have a ROM image for the NEC PC-8300? This is NEC's variant of the Kyocera KC 85, of which the TRS-80 Model 100 was another. I picked up two of these a long time ago, they had been used as some sort of data-logging system and had custom ROMs in them which are useless without special hardware I don't have :). Now that I have a functional EPROM burner I can get this running in its native state, if only I can find the right ROM for it. Can't seem to find this on the 'net. Thanks for any pointers... Josh ----------Reply: Go to: http://www.diginexus.com/web8201/ and get in touch with Gary at the link there; he's Mr. NEC and will have it for you and he's also a nice guy who'll gladly help you with any other NEC issues you may have. mike

18 years, 8 months

2
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Almost OT: Pushbutton switch latching

by dm561＠torfree.net

-----------Original Messages: Date: Thu, 6 Dec 2007 22:06:49 -0800 From: dwight elvey <dkelvey at hotmail.com> Subject: RE: Almost OT: Pushbutton switch latching > From: ian_primus at yahoo.com > The main thing I'm trying to achieve is simplicity. > Nothing fancy. No PIC's, no microcontrollers, etc. I > initially thought of using flip flops and a bunch of > inverters to reset all the non-selected flip flop, but > couldn't work out in my head a good way to do it... I > hadn't taken switch debouncing into the equation - but > aren't flip flops commonly used to debounce switches > anyway? > Hi The simplest method would be to use the cross coupled nands as another described. For 8 inputs, you'll need 4 ea 7400's to make the nand latches. You'l need 8 ea 8 input nands ( forget the 74 number ) and 3 of the hex inverters, 7404s. For each switch wire one lead to ground. Wire one lead to a 4.7K pullup resistor and one of the free inputs to the cross coupled nand pair. Also wire that switch lead to 7 of the 8 input nands ( not the one on this switch circuit. ). On the remaining free inputs to the cross coupled nands pair, wire an inverters output. The input of the inverter goes to the output of the 8 input nand that wasn't one of the 7 connected to this switch. Repeat this for each of the 8 switches. If the active level is to be 0 when selected, you can save one inverter IC. If it needs to be active high, you need the inverter. in either case, you need to connect to the nand that has the inverter to the 8 input nand. This will ensure that multiple switches won't select anything until only one is selected. On the 8 input nand, you'll notice that one input isn't connected. This can be used to reset. Tie all together with a 1K resistor to +5. Place a diode across this such that the band is on the +5 ended. Add a 10uf tantalum to this net with th plus on the same net and the negative to ground. This will reset all on powering up. If you want to one of the outputs to come on when powering up, you can add a similar capacitor, resistor and diode circuit to the desired input switch lead. You'd need to remove the common input to the 8 input nand and tie it to +5 as well. I like this better than using some other clocked method because if multiple switches are selected at the same time, non will select but when the last switch is still selected, that output will go active. There are no ambiguous states and no oscillations. The switches are debounced as well. Dwight ------------Reply: 15 ICs and a dozen discretes is "the simplest?" I think some simpler circuits have been suggested...;-) As a matter of fact, if you add a diode & cap per switch you could do the job with 2 IC's for each 8 PBs (7430 & '573 (or 2x'75 if you need complementary outputs)). mike

18 years, 8 months

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Haletine 2000 ? was Re: Hazeltine 1200

by dm561＠torfree.net

Date: Sun, 09 Dec 2007 15:55:19 -0500 From: "Roy J. Tellason" <rtellason at verizon.net> Subject: Re: Haletine 2000 ? was Re: Hazeltine 1200 To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <200712091555.19523.rtellason at verizon.net> Content-Type: text/plain; charset=iso-8859-1 On Sunday 09 December 2007 15:47, Richard wrote: >> In article <ded268c40712091038offab0fbg2bc611169d5c55b7 at mail.gmail.com>, >> >> "Paxton Hoag" <innfoclassics at gmail.com> writes: >> > So if you see one expect to pay for it. >> >> I had to outbid other Crommeco collectors for the Beehive. $350. >Dang! That Cromemco 3101 (?) I have sitting in storage is worth that much? >Whodathunkit... --------- And I gave one away... Lesson learned! m

18 years, 8 months

1
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Yet Another VT-100 Emulator

by dave06a＠dunfield.com

Hi Guys, Just thought I'd mention in case anyone is interested... Having recently acquired a couple of VAXen, I've taken the time to update my LAPTALK terminal program to provide MUCH more complete VT-100 emulation. This is a very small (<20k) DOS program, so you can use it to turn any old PC into a terminal. First the bad news - Like most PC/text based VT-100 emulators, it DOES NOT support: - Double width/Double height lines. - 132 column mode. - Split RX/TX speeds. The good news - It does support "most everything else" now. In fact, it's the only emulator I've tested which passes all of my "VT-100 Checkup" tests (excepting for the limitations mentioned above) - I've included the test program in the archive. It also adds a few extra features you might find useful: - Fairly power script language for automating sessions. - 40 programmable function keys (F1-F10, ShiftF1-F10, CtrlF1-F10 and AltF1-F10) with on-screen labels. (very handy!) - If you have a VGA display it will load a custom character set to provide the complete VT-100 character set including the graphics mode characters. I've also include a font editor so that you can create your own custom character sets if you like. I've made the package temporarily available at: http://www.dunfield.com/pub/index.htm If there's any interest, I'll find it a permanent home. Regards, Dave -- dave06a (at) Dave Dunfield dunfield (dot) Firmware development services & tools: www.dunfield.com com Collector of vintage computing equipment: http://www.classiccmp.org/dunfield/index.html

18 years, 8 months

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CDC 5 1/4 floppy 77711501 / 77711800 specs

by g-wright＠att.net

-------------- Original message from Fred Cisin <cisin at xenosoft.com>: -------------- > On Sun, 9 Dec 2007 g-wright at att.net wrote: > > Hi > > I have a machine with a 77711501 floppy drive and it's bad.. I have > > tried 3 different 360k drives. I tried to find specs on it but so far have > not. > > What is the difference between that drive and a 77711800 used in a PC > > The computer just says there is a drive error. I'm using the same jumper > > settings on both. I have also tried a Teac fd-55bv. > > Is it a 320k drive ?? > > There ain't no difference. > 320K drive and 360K drive are the same drive. > > There is a way that it would be possible to build a drive that could do > 320K, but not be able to do 360K, but nobody has done so yet. > > Boot something other than WINDOZE. "Drive error" is not specific enough. > > > And for the rest of the story ..................... This is on a MicroStar machine that runs StarDos. I know nothing about this but from recent posts I decided to drag one of them down and look into it a little further. This machine I have running is a Micro Five 1000 with a IMI 10 meg HD. It has a boot menu and back up Menu. It will still boot and will make its own formatted floppies and back itself up with out much problems. If I try to read one of the floppies with Image disk or Anadisk they fail. It tried with both 360 and 1.2 meg drives. I would guess that the drive in the machine is off enough to cause these problems . If I install another floppy drive, the System picks up something and errors. So there must be some other signal or ??? coming from the drive. The machine date is in the 84 -85 range The straps on the drive (M 4 x 3 2 1 H) are set with M and 1 jumpered - thanks, Jerry

18 years, 8 months

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Almost OT: Pushbutton switch latching

by dm561＠torfree.net

------------Original Message: Date: Sat, 08 Dec 2007 23:50:29 -0800 From: "Chuck Guzis" <cclist at sydex.com> Subject: Re: Almost OT: Pushbutton switch latching On 9 Dec 2007 at 0:15, der Mouse wrote: > Nice idea, but it doesn't work. Draw out three NANDs cross-coupled as > you described. Mark the logic states for a stable state with one > output low. Now consider what happens when each of the inputs goes > low. The only one that does anything is the one feeding the gate whose > output is low. Yeah -- I see that. Release a button and the circuit goes into an unstable state. I wonder what the smallest number of active devices is for an n-stable circult with n greater than 2. 8 D flip=flops with each switch connected to a PRESET input and a NAND (or NOR) to edge-clock in a reset state looks to be far from the minimum. How about some capacitively coupled logic with a few steering diodes? Cheers, Chuck ---------------Reply: Well, with some diodes and caps, a single 8-bit latch (74564/574) oughta do the job. m

18 years, 8 months

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Free Magazines. was: Electronics Today International back issues

by Nick.Jarmany＠quixant.co.uk

Hi Rob, You may not remember but you posted the following on classiccmp.org about 2 years ago:- >I have a large pile of magazines dating back to the 70's-mid 80's, mostly >Hobby Electronics right from the start, quite a lot of ETI (but I don't >think as late as wanted here, box is buried behind a live server so will >take time to access and check) also a lot of Practical Electronics >including, if I still have them, many dating back to the '60s. Lots of >odds and ends too as to be expected, plus I think some Railway Modeling >mags to stray off topic.. I am writing this email on the off-chance you might still have these. I grew up with ETI as a child and kept all my magazines from mid-70?s until mid-80?s but unfortunately they were all thrown out when my parents moved house. I found your post (and the classiccmp.org forum ) from a Google for Electronics Today International. I am trying to get hold of as many of the magazines from this era as possible. I am particularly hoping to be able to find the issues that covered the ETI System68, which I built when I was 16. Ideally I would like to find these and get them scanned, approach the current copyright owners and see if they would agree to PDF?s of these magazines being made available online. I would also like to try and re-build this design if at all possible. Anyway, hope to hear from you. Regards, Nick Jarmany London No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.503 / Virus Database: 269.16.17/1177 - Release Date: 07/12/2007 13:11

18 years, 8 months

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got this old peecee...

by rtellason＠verizon.net

And a few things I've noticed about it are: -- It says "digital" (lowercase like that) on the front. :-) -- it has a third power supply connector to the MB, and that PS is rated to ptu 33A (!) out on the +5 -- It has the CPU on a separate small daughterboard. A jumper there seems to select speeds, up to maybe 100 or so. I have a 486dx2/66 chip in it at present, which will run real flaky at 80, and not at all at 100. :-) -- It has a _very_ loud beep when you power it up. -- It wants only _parity_ ram -- there's no option in CMOS to disable that. I have a couple of 16s and a couple of 4s in there at present, all the parity parts I was able to scrounge. Anybody have some they might wanna trade? -- Slots are ISA only, but they're _all_ 16-bit. -- This thing's built like a tank! I'd originally planned to put OS/2 in this box. Now I'm lots less enthused about that OS than I was at one time, so I dunno what I'm gonna do with it. Thoughts on this? -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin

18 years, 8 months

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Scan of a 1702A

by grant＠stockly.com

I couldn't help it. I had to scan a 1702A 256byte EPROM. This one was done at 6400dpi, really 3200dpi along the scanner array and 6400dpi in the scanning direction. So there is some interpolation in the image. Still a pretty impressive picture for a scanner. :) http://www.stockly.com/images3/071208-1702A-1.jpg Just playing the new scanner... Grant

18 years, 8 months

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4
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Teaching kids about computers... (CoCo assembler)

by mtapley＠swri.edu

At 18:28 -0600 11/28/07, Sean wrote: > A Color Computer or Color Computer 2 seems to fit the bill. The CPU is >the nicest of the 8bits (IMHO) and the video screen is more logical than >anything you'll find on the C64, Atari or Apple. ... At 18:28 -0600 11/28/07, Mark M. wrote: >I'd tend to agree. The 6809 is a lovely processor, and there aren't any of >the "black box" chips that others have mentioned. ... I'd agree completely, *except* that if you want to do Assembly (conveniently), you also need the EDTASM+ ROM cartridge, and prices/availability for those seem to have gone a little wonky in the past 6 months. EBay prices yield systems for $5 to $10 (plus shipping), but the EDTASM cart is over $30. I have not found a non-eBay source that actually had a cart for sale at all. I don't quite have the knowledge to do it, but something I'd really like to see is a reverse-engineered equivalent (editor, assembler, monitor) implemented and available as an inexpensive cassette tape or downloadable sound file that could be played into the cassette port (or even, shudder, READ-DATA/POKE basic program to type in) and an accompanying public-domain manual. I know this would be vulnerable to getting overwritten by an out-of-control assembly program, and the ROM version is preferable, but it sure would turn a cheap, otherwise very capable BASIC platform into a cheap, very capable Assembly language platform that one occasionally had to re-load. I note that there are good emulators and cross-compilers available for both Mac OS-X and Windows: Toolshed for OS-X rocks: http://sourceforge.net/projects/toolshed/ David Keil's Windows emulator gets excellent reviews: http://www.discover-net.net/~dmkeil/index.htm no relation either way. -- - Mark, 210-379-4635 ----------------------------------------------------------------------- Large Asteroids headed toward planets inhabited by beings that don't have technology adequate to stop them: Think of it as Evolution in Fast-Forward.

18 years, 8 months

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FW: GAL16V8 as a modern substitute for a 7447?

by dm561＠torfree.net

------------Original Message: Date: Sat, 8 Dec 2007 18:30:43 +0000 From: Ethan Dicks <ethan.dicks at usap.gov> Subject: Re: GAL16V8 as a modern substitute for a 7447? On Sat, Dec 08, 2007 at 08:12:30AM -0800, Peter C. Wallace wrote: > On Sat, 8 Dec 2007, Ethan Dicks wrote: > >Has anyone here worked with or ever plotted silently to create a moderish > >7-segment decoder/driver from a GAL16V8? > > IICRC the 16V8 does not have buried registers so you will lose the 4 of the > output pins (for the counter) that you needed for the 7 segment outputs Right. > If you are using sockets, a 5V or 3.3V (cheaper) 44 pin PLCC CPLD might be > a better solution, plus they are easier to program. A X9572XL will probably > do 4 decades of count/decode for about $2.00 That is not feasible. I need 7 or 9 decades of count/decode, and I happen to have an abundance of GALs and a GAL programmer. If it comes down to a CPLD-design, I'll probably throw in the towel and use an AVR microcontroller and perhaps a real 74LS47 or 74LS247 to lower the I/O requirements a touch. I was just musing about what it might take to put it all in hardware rather than a combination of hardware and firmware. Using an MCU makes the entire problem trivial. Thanks, -ethan ----------------- --------------Reply: Well, since it started one of "those" discussions here as usual anyway, what's wrong with a 74143? mike

18 years, 8 months

4
3
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FAA control room keyboard -- parallel or RS-232?

by legalize＠xmission.com

I have an FAA control room keyboard that I picked up off ebay. Each key has a little bulb underneath it that lights up the keys for use in the dark. I need to get some replacement bulbs since some of them have burned out. I haven't disassembled this thing enough to know if they have parts numbers on them or not. Does any of this sound familiar to anyone? I'm thinking that the bulbs burning out has got to be a regular occurrence and that the bulbs are therefore probably socketed and not soldered, but again I didn't disassemble it that far to know. The keyboard assembly inside is labelled MicroSwitch IIRC. -- "The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download <http://www.xmission.com/~legalize/book/download/index.html> Legalize Adulthood! <http://blogs.xmission.com/legalize/>

18 years, 8 months

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CDC 5 1/4 floppy 77711501 / 77711800 specs

by g-wright＠att.net

Hi I have a machine with a 77711501 floppy drive and it's bad.. I have tried 3 different 360k drives. I tried to find specs on it but so far have not. What is the difference between that drive and a 77711800 used in a PC The computer just says there is a drive error. I'm using the same jumper settings on both. I have also tried a Teac fd-55bv. Is it a 320k drive ?? - jerry

18 years, 8 months

3
2
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Apple StyleWriter M8000

by glade＠barneygang.com

Since our printer has malfunctioning and not working and I am interested in getting a printer for my computer and the M8000 is what we need. If your Stylewriter printer is working, we would be happy to pay the shipping to have it shipped here. My email is: glade at barneygang.com

18 years, 8 months

1
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HP250 curiosity

by blstuart＠bellsouth.net

> In the case of the HP41 calculator, it was physcially impossible to run > machine code from the machine's internal RAM. The processor was a pseudo > harvard architecture, RAM was organised in 56 bit 'registers' connected > to the SPU DATA line, ROM was in 10 bit words connected to the ISA line. > Some hackers found a way round this, making ROM emulator boxes (normally > called MLDL (Machine Language Development Lab) units). Where does the synthetic programming fit in? I thought it was a case of creating machine language code in RAM. And I remember it being based on some ugly tricks, rather than an external device. BLS

18 years, 8 months

2
2
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Listing paper FTGH (Yorks, UK)

by listmailgoeshere＠gmail.com

Hi list, I have 7 2000-sheet boxes of tractor-feed plain 11x14.5" listing paper which I'd like to give away as I need the space back. Located in West Yorkshire, UK. Sorry, it isn't greenbar ;) There are also 3 boxes of A4-ish size (11x9.5" I think they are). Free, but you'll have to collect. I'd ship if you're desperate, but it won't be cheap as they're heavy. Please drop me a mail if you're interested - thanks. Ed.

18 years, 8 months

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GAL16V8 as a modern substitute for a 7447?

by lee＠geekdot.com

>> One thought was to attempt to combine a 7490 _and_ a 7447 in a single >> GAL16V8. I have blown hundreds of PALs, but have much less experience > IICRC the 16V8 does not have buried registers so you will lose the 4 > of the output pins (for the counter) that you needed for the 7 segment > outputs You can do it but you need to make a counter that counts in segment patterns and not binary. I did see an example of this and remember thinking how clever it was but a search of my files and online has failed to turn up a copy. Lee.

18 years, 8 months

2
1
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TRADIC

by evan＠snarc.net

>>> Camp Evans was just a small part of the Signal Corps. It was not the center, by any means. I never said otherwise. BUT, in all of the examples I've cited, the sources indicated not just the Signal Corps lab, but specifically the Signal Corps comms lab at Fort Monmouth. That's us (there is plenty of other evidence too, but we're already OT for cctalk ... feel free to carry this over to the local club list.)

18 years, 8 months

1
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GAL16V8 as a modern substitute for a 7447?

by lee＠geekdot.com

> I found a fleeting reference, perhaps, in the ORCAD 4.0 manual, > chapter 5, on PLDs? > |GAL16V8 in:RESET, > | out:(SEG[6~0], CARRY), Yes that looks like it. So at least I wasn't imagining it. Lee.

18 years, 8 months

1
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(no subject)

by lee＠geekdot.com

> Hmm... Having said all that, it might be possible to put a state > machine into a 16V8 that had a 7 bit current state and a next state > function that corresponded to "counting" is seven segments. It was just that that I've seen an example of, many years ago, but can't find now. Lee.

18 years, 8 months

2
1
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Almost OT: Pushbutton switch latching

by lee＠geekdot.com

> 8 74xx30's (8 input NAND) with each output feeding one of the inputs > of the other stages. That was my first thought but a quick look at the logic revealed that pressing one button will make only one of the other seven outputs go low. Lee.

18 years, 8 months

1
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Information on the AtariLab Interface

by chaosotter76＠gmail.com

It took me longer than I meant to, but I dug up the manual for the AtariLab package that I'd mentioned in the thread on getting kids into older computers. In case you weren't reading that discussion, the AtariLab system was a science kit for the Atari 8-bit home computers that included a cartridge, an interface box that plugs into the joystick port, and a variety of measurement probes. Atari must have manufactured them far in excess of demand (no! not Atari!), because they're still fairly inexpensive NIB. At any rate, here's the scoop on the interface box: it has 8 phono jacks on it, arranged into 4 pairs: PADDLE, PTRIG, CONTROL, and POWER. The PADDLE inputs are the analog inputs; they're simply expecting to see a variable resistor on the other end, just as you'd except. The PTRIG inputs are digital inputs corresponding to the joystick fire buttons. The CONTROL jacks are indeed digital outputs (this was the question that came up in the original thread). They are wired to the UP and DOWN pins of the connector -- the Atari joystick interface can be programmed to use these pins for output rather than input, it seems. You must use controller jack 3 or 4 on the original 400/800 and 1 or 2 on the XL series. The PTRIG inputs can be reversed in the same way, giving you a total of four digital output lines per interface. The POWER outputs are just connected to the +5V supply of the joystick interface. The manual doesn't indicate how much current you can draw from the interface, but I imagine it's not much. So there you have it: 2 analog inputs, 2 digital input/outputs, 2 digital outputs, and 2 power connections.

18 years, 8 months

5
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TRADIC

by evan＠snarc.net

For me, this is exciting because the early transistor research was (to a large extent) encouraged and funded by the Army Signal Corps lab that is now the home of our computer museum. Yes, Will D., we know for FACT that it was our lab and not just the ASC in general. Will likes to keep us on our toes. :) Speaking of which -- sorry for the thread hijack -- at the next VCF East we will have a special exhibit of all the computer history that happened or that was directly related to our lab. Bush, Mauchly, Hewlett, Vollum, Shockley -- they all are part of our history here. (Which makes it quite fun for us to roam the hallways looking for ghosts!) -----Original Message----- From: Brent Hilpert <hilpert at cs.ubc.ca> Subj: Re: TRADIC Date: Sat Dec 8, 2007 2:04 am Size: 1K To: General at priv-edmwaa05.telusplanet.net; "Discussion at priv-edmwaa05.telusplanet.net":On-Topic and Off-Topic Posts<cctalk at classiccmp.org> Evan wrote: > > A few days ago, someone asked about TRADIC. Tonight I stumbled upon a mention of this computer on page 204 of the book "Crystal Fire" (Michael Riordan and Lillian Hoddeson, 1997). The authors wrote, "In January 1954 Whippany engineers built a fully transistorized computer for the Air Force. Called TRADIC (for TRAnsistorized DIgital Computer), it used 700 point-contact transistors and more than 10,000 germanium crystal rectifiers in its circuits. Capable of performing a million logical operations every second, TRADIC was the first completely solid-state computer; it approached the speed of computers based on vacuum tubes." > > By "Whippany" they meant the Whippany, N.J. location of Bell Labs. TRADIC is a well-known machine in the history of computing. A little googling does bring up a lot of refs. (I think there's another experimental/proof-of-concept machine commonly mentioned as being one of the first transistorised machines (something from Philco perhaps?).) Another anecdote I ran across a few years ago in the IEEE AotHoC (which I wish had kept a ref to), was of an IBM engineer working on one of the first transistorised designs in the mid-50s (ECL IIRC), telling the story of how he chose 5 Volts for the logic supply.

18 years, 8 months

2
1
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OT: Vintage sighting

by cclist＠sydex.com

I'll make this quick--I just saw a rerun of a 1970 "Mission Impossible" episode called "The Innocent". The computer there definitely looks to be Univac; I'm guessing an 1106. Anyone else see this one? ...and who has a reference manual for KAZAN IV? Cheers, Chuck

18 years, 8 months

2
1
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HP250 curiosity

by cclist＠sydex.com

I was going through some of my old literature and stumbled upon a discussion of the HP250 architecture. One statement made was that it was impossible for the customer to write his own binary executables on this system. The idea being that the customer would program everything in HP BASIC, I imagine. Out of curiosity, was this restriction ever relaxed? How many people have one of these in their collection? Cheers, Chuck

18 years, 8 months

4
3
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OT: Need Sparcstation 5 rescue

by us21090＠yahoo.com

All- In an appeal to avoid the crusher.... I've got an SUN/Sun Sparcstation 5, GDM-1662B monitor (16" specs say, 1280 x 1024, color), 13W3 video cable, keyboard, mouse, 64 MB, 1 GB drive (I believe). I live near BWI, Maryland. If you know someone (who knows someone)* who would like this system, let me know. BTW, that previous line is a joke of sorts for the regular expressionists among us. I'd prefer a local pickup, but will ship on your nickel. Thanks, Scott ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ

18 years, 8 months

1
0
0 0

Torode disk controller for the S-100

by dwight＠svdc-imap00.amd.com

Hi Bob Do you remember the S-100 controller and disk drives I talked you into buying last year? I recently dug up some more interesting information. I've actually found someone that has a manual. This is a find. These controllers are really quite rare. Manuals are even rarer. Second thing is that these Digital Systems controllers were designed by Torode. These were the first S-100 floppy system that Kildall release a packaged CP/M for. I knew these were early controllers but didn't realize the history of them. Dwight

18 years, 8 months

3
4
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Northgate OmniKey Ultra

by jkbla＠sbcglobal.net

Hi, I saw this whilst doing some searches. Do you still have it? Response appreciated. Thanks

18 years, 8 months

1
0
0 0

CNN front page: Commodore 64

by dzubint＠vcn.bc.ca

So, I turn on the computer this morning, go to www.cnn.com to see the latest Britney Spears news ('cause CNN reports on ALL of the important stuff like that) and what do I see on the front page? A Commodore 64 story! http://www.cnn.com/2007/TECH/ptech/12/07/c64/index.html Thomas "PDP-11" Dzubin Calgary, Vancouver, or Saskatoon

18 years, 8 months

6
5
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Hazeltine 1200

by ploopster＠gmail.com

My father just rescued a Hazeltine 1200 from a scrapheap for me. I know nothing about these. Could someone give me some pointers to information? Thanks. Peace... Sridhar

18 years, 8 months

7
17
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Free "museum pieces" in London

by lproven＠gmail.com

A message I spotted on the CIX online service... [[ >From Hex Museum pieces Before they go into a skip, does anyone want: Amstrad PC1512 with dual floppies BBC model B with microvitec monitor and twin 5.25" floppies Epson EX-100 132-column printer Epson FX-80 Sinclair ZX Printer Collect from Edgware, nw London. Feel free to copy this elsewhere. If you want anything, email robert at schifreen dot co dot uk ONLY. ]] -- Liam Proven ? Profile: http://www.linkedin.com/in/liamproven Email: lproven at cix.co.uk ? GMail/GoogleTalk/Orkut: lproven at gmail.com Tel: +44 20-8685-0498 ? Cell: +44 7939-087884 ? Fax: + 44 870-9151419 AOL/AIM/iChat: liamproven at aol.com ? MSN/Messenger: lproven at hotmail.com Yahoo: liamproven at yahoo.co.uk ? Skype: liamproven ? ICQ: 73187508

18 years, 8 months

4
4
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Offered: Free Macs, London, England

by lproven＠gmail.com

I'm trying to have a clear out and I think it's time most of the legacy Mac stuff went. I have: - 2 LC 475s (one dead, one alive, as far as I can recall) - one PowerMac 6100/66 (runs but has a blank hard disk) - one Beige G3 minitower (300MHz, CD, Zip, 8GB HD) - UMAX PPC604 Mac compatible minitower machine I've also got at least 1 21" mono Mac monitor with accompanying mono NuBus graphics card, 1 or 2 14" Apple colour monitors, and a couple of boxes of classic Mac apps. Anyone who wants any or all of these machines, including some free apps to go with them, is welcome to come and rummage. -- Liam Proven ? Profile: http://www.linkedin.com/in/liamproven Email: lproven at cix.co.uk ? GMail/GoogleTalk/Orkut: lproven at gmail.com Tel: +44 20-8685-0498 ? Cell: +44 7939-087884 ? Fax: + 44 870-9151419 AOL/AIM/iChat: liamproven at aol.com ? MSN/Messenger: lproven at hotmail.com Yahoo: liamproven at yahoo.co.uk ? Skype: liamproven ? ICQ: 73187508

18 years, 8 months

1
0
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Need NDIS2SUP.386 file for Windows for Workgroups

by sellam＠vintagetech.com

Ok, I give up. I've searched high, low, sober, etc., and cannot find one single solitary instance of the file NDIS2SUP.386. It is supposedly on Disk 7 of the WFWG install set. I have a set that has 8 disks but the file is nowhere to be found on any of them. I've found references to the file WG0971.EXE which should be a self-extracting file that contains NDIS2SUP.386 but it cannot be found, not even where it should be on Microsoft's FTP server. I spent hours on Google and it is not there. Maybe someone else has more Google foo than me, and you're welcome to try, but I'll bet someone out there has this file. If so, PLEASE e-mail me directly to let me know. Thanks a thousand times in advance and may all your dreams be naughty. -- Sellam Ismail Vintage Computer Festival ------------------------------------------------------------------------------ International Man of Intrigue and Danger http://www.vintage.org [ Old computing resources for business || Buy/Sell/Trade Vintage Computers ] [ and academia at www.VintageTech.com || at http://marketplace.vintage.org ]

18 years, 8 months

3
4
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HP 9000/216

by pat＠computer-refuge.org

I finally decided to pick up the HP 9000/216 box which had been laying around at my usual supplier for a few weeks. I spent a little time looking at google, and can't find much info on them. >From physical examination, it looks like it has a 1MB and a 256kB expansion memory card (so 1.5MB total), and a fairly large keyboard, which is different than the "standard" keyboard that comes with it (it includes a dial at the top left, and has grey keys instead of brown). I was wondering if these are actually somewhat rare, or if they're just not very well sought-after. If anyone is interested in giving me some $$ for one or has something interesting (mostly old DEC), feel free to bother me about it. Pat -- Purdue University Research Computing --- http://www.rcac.purdue.edu/ The Computer Refuge --- http://computer-refuge.org

18 years, 8 months

9
16
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Free "museum pieces" in London

by mike＠brickfieldspark.org

> From: Pete Turnbull <pete at dunnington.plus.com> > Subject: Re: Free "museum pieces" in London > > I'm pretty sure it is, and that might even be the Beeb he used. I have > the modem :-) > >> robert at schifreen dot co dot uk schifreen dot co dot uk goes to http://www.defeatingthehacker.com/securitysavvy/ Which states - " In 1985, Robert became the first person in the world to face a jury trial in connection with computer hacking. His ultimate acquittal on all charges led to the introduction of the UK's Computer Misuse Act 1990, which now outlaws the practice. " Mike

18 years, 8 months

1
0
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Almost OT: Pushbutton switch latching

by dm561＠torfree.net

Message: 17 Date: Thu, 06 Dec 2007 18:16:44 -0500 From: "Roy J. Tellason" <rtellason at verizon.net> Subject: Re: Almost OT: Pushbutton switch latching To: "'cctalk at classiccmp.org'" <cctalk at classiccmp.org> Message-ID: <200712061816.44523.rtellason at verizon.net> Content-Type: text/plain; charset=iso-8859-1 On Thursday 06 December 2007 11:24, M H Stein wrote: >> Date: Wed, 05 Dec 2007 17:55:51 -0800 >> From: "Chuck Guzis" <cclist at sydex.com>> >> Subject: Re: Almost OT: Pushbutton switch latching >> >> (No "almost" about it any more...) >> >> >On 5 Dec 2007 at 17:35, Fred Cisin wrote: >> >> . . . then I guess that a rotary telephone dial is out of the question >> > >> >Oooh, cool--Strowger switches! > >> ------------- >> Pshaw; a mere 10 positions? I've got a 25-step 12-pole stepper here, >> just the ticket. Expandable? I'll say; add one of your 10-steps and you've >> got 250 positions. >(Trying to picture a 25-hole old-style telephone dial... :-) ------------- Think bigger - the interrupter doesn't care how many! Or dial 10 at a time... m

18 years, 8 months

1
0
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Almost OT: Pushbutton switch latching

by dkelvey＠hotmail.com

> From: ian_primus at yahoo.com > > I guess I should have been more clear... And everyone > has brought up some good points. I initally didn't > think about the initial power-up setting, but in this > application it doesn't much matter - I guess > defaulting to none pressed (or #1 pressed, even > better) would be good. I don't intend to press two > switches at once, but if it were to happen, it doesn't > much matter - either one could take priority. I'd > rather not have more than one select output active at > a time, but it's not a huge problem if it happens. > Timing is totally non-critical. Two outputs can be > active for a tiny period, no outputs active during > switching is fine. The idea is to simply control some > CBT3244A bus switching chips to switch some analog > signals. I want to avoid having each chip controlled > by a toggle on/off switch, because then in order to > change signals you would have to manually turn off > one, and turn on the next. > > The main thing I'm trying to achieve is simplicity. > Nothing fancy. No PIC's, no microcontrollers, etc. I > initially thought of using flip flops and a bunch of > inverters to reset all the non-selected flip flop, but > couldn't work out in my head a good way to do it... I > hadn't taken switch debouncing into the equation - but > aren't flip flops commonly used to debounce switches > anyway? > Hi The simplest method would be to use the cross coupled nands as another described. For 8 inputs, you'll need 4 ea 7400's to make the nand latches. You'l need 8 ea 8 input nands ( forget the 74 number ) and 3 of the hex inverters, 7404s. For each switch wire one lead to ground. Wire one lead to a 4.7K pullup resistor and one of the free inputs to the cross coupled nand pair. Also wire that switch lead to 7 of the 8 input nands ( not the one on this switch circuit. ). On the remaining free inputs to the cross coupled nands pair, wire an inverters output. The input of the inverter goes to the output of the 8 input nand that wasn't one of the 7 connected to this switch. Repeat this for each of the 8 switches. If the active level is to be 0 when selected, you can save one inverter IC. If it needs to be active high, you need the inverter. in either case, you need to connect to the nand that has the inverter to the 8 input nand. This will ensure that multiple switches won't select anything until only one is selected. On the 8 input nand, you'll notice that one input isn't connected. This can be used to reset. Tie all together with a 1K resistor to +5. Place a diode across this such that the band is on the +5 ended. Add a 10uf tantalum to this net with th plus on the same net and the negative to ground. This will reset all on powering up. If you want to one of the outputs to come on when powering up, you can add a similar capacitor, resistor and diode circuit to the desired input switch lead. You'd need to remove the common input to the 8 input nand and tie it to +5 as well. I like this better than using some other clocked method because if multiple switches are selected at the same time, non will select but when the last switch is still selected, that output will go active. There are no ambiguous states and no oscillations. The switches are debounced as well. Dwight _________________________________________________________________ Connect and share in new ways with Windows Live. http://www.windowslive.com/connect.html?ocid=TXT_TAGLM_Wave2_newways_112007

18 years, 8 months

1
0
0 0

Tandy with expansion for jay

by g-wright＠att.net

-------------- Original message from "Jay West" jwest at classiccmp.org>: --------- Jay I have walked over this tandy long enough. send me your address Before is heads out the door. - Jerry Jerry Wright JLC inc g-wright at att.net

18 years, 8 months

1
0
0 0

Almost OT: Pushbutton switch latching

by dm561＠torfree.net

Date: Wed, 05 Dec 2007 17:55:51 -0800 From: "Chuck Guzis" <cclist at sydex.com> Subject: Re: Almost OT: Pushbutton switch latching (No "almost" about it any more...) >On 5 Dec 2007 at 17:35, Fred Cisin wrote: >> . . . then I guess that a rotary telephone dial is out of the question >Oooh, cool--Strowger switches! ------------- Pshaw; a mere 10 positions? I've got a 25-step 12-pole stepper here, just the ticket. Expandable? I'll say; add one of your 10-steps and you've got 250 positions. mike

18 years, 8 months

2
1
0 0

Hazeltine 1200

by ajp166＠bellatlantic.net

> >Subject: Hazeltine 1200 > From: Les Hildenbrandt <les at hildenbrandt.com> > Date: Thu, 06 Dec 2007 07:40:14 -0700 > To: cctech at classiccmp.org > >My first computer came with a Hazeltine 1000, this was older than the >1200. It had 80 characters wide, but I think it only was 12 lines tall, I remember it as 72 (tty width). >I cant remember that part for sure. What I remeber for sure was that it >was upper case only. There was a place of the PCB for a second >character generator rom for lower case which was not loaded. There was >also a switch on the front which enabled lower case for the keyboard. >That was very confusing because sometimes I was typing in lower case, >then when I did a search or search / replace in ed it couldn't find what >I was searching for because it was upper case. I didn't figure that out >until later when I got an intertube terminal to replace the Hazeltine 1000. ;) Allison >Les

18 years, 8 months

1
0
0 0

Hazeltine 1200

by ajp166＠bellatlantic.net

> >Subject: Re: Hazeltine 1200 > From: Sridhar Ayengar <ploopster at gmail.com> > Date: Thu, 06 Dec 2007 10:09:00 -0500 > To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> > >Allison wrote: >>>> My father just rescued a Hazeltine 1200 from a >>>> scrapheap for me. I know >>>> nothing about these. Could someone give me some >>>> pointers to >>>> information? Thanks. >>>> >>> Nice! I don't know anything about the 1200, but I have >>> a 1500 and a 1421. They are both just simple >>> terminals, with some fairly basic control functions >>> What does it look like? Is the keyboard integral or >>> detatched? Does it look like the 1500/1400 series? - >> >> The 14xx and 15xx are late 70s (after 1976) as 1500 used >> 8080 and the 1400 used 8048 cpus. > >Interesting. 8048 is an integrated microcontroller, no? Yes but it has an external databas and addressing for extended configurations. Basically a subset of 8051. Allison >>> http://vt100.net/manx/covers/14/hi-1056a.png. >>> >>> Now, if it looks like the 2000, you've got a great >>> score. Those are some interesting beasts. I've never >>> seen one, but they look like this. >>> http://www.columbia.edu/acis/history/h2000s.gif >>> >>> The Hazeltine 2000 was a very early video terminal >>> (circa 1972). >> >> The 1200 was a basically glass tty, all uppercase >> (may have had a back pannel option for all upper >> tty mode or mixed) it was capable of slow baud rates >> (I think to 1200 or 4800) and both RS232 or current >> loop. I used on on the DEC PDP10 so that means it >> was in house there by spring 1972. It was all logic >> no cpu used and I belive it used serial PMOS shift >> registers for storage. > >Wow. Neato! > >Peace... Sridhar

18 years, 8 months

1
0
0 0

Hazeltine 1200

by ajp166＠bellatlantic.net

> >Subject: Re: Hazeltine 1200 > From: Dave McGuire <mcguire at neurotica.com> > Date: Thu, 06 Dec 2007 09:24:29 -0500 > To: "General Discussion: On-Topic Posts Only" <cctech at classiccmp.org> > >On Dec 5, 2007, at 10:02 PM, Sridhar Ayengar wrote: >>>> My father just rescued a Hazeltine 1200 from a scrapheap for me. >>>> I know nothing about these. Could someone give me some pointers >>>> to information? Thanks. >>> Nice! Let us know the date codes on the chips when you get a chance >>> to peek inside. >> >> Will do. > > I'm also curious about what processor it's built around, if you >don't mind checking. Best of my knowledge only the 15xx and 24xx serius used a processor and the earlier ones wer random logic and simple state machines. Allison > > -Dave > >-- >Dave McGuire >Port Charlotte, FL >Farewell Ophelia, 9/22/1991 - 7/25/2007 > >

18 years, 8 months

1
0
0 0

Hazeltine 1200

by ajp166＠bellatlantic.net

> >Subject: Re: Hazeltine 1200 > From: Dave McGuire <mcguire at neurotica.com> > Date: Thu, 06 Dec 2007 10:33:17 -0500 > To: "General Discussion: On-Topic Posts Only" <cctech at classiccmp.org> > >On Dec 6, 2007, at 10:09 AM, Sridhar Ayengar wrote: >>>>> My father just rescued a Hazeltine 1200 from a >>>>> scrapheap for me. I know nothing about these. Could someone >>>>> give me some >>>>> pointers to information? Thanks. >>>>> >>>> Nice! I don't know anything about the 1200, but I have >>>> a 1500 and a 1421. They are both just simple >>>> terminals, with some fairly basic control functions >>>> What does it look like? Is the keyboard integral or >>>> detatched? Does it look like the 1500/1400 series? - >>> The 14xx and 15xx are late 70s (after 1976) as 1500 used >>> 8080 and the 1400 used 8048 cpus. >> >> Interesting. 8048 is an integrated microcontroller, no? > > Yes it is; sorta a predecessor to the 8051 family. Yes, and it can also address up to 4k of program either internal (up to 2K for the 8049) and axternal. It's possible to hand external ram on it as well but the pointer is only 8bits so larger ram has to be paged using IO pins. Allison > -Dave > >-- >Dave McGuire >Port Charlotte, FL >Farewell Ophelia, 9/22/1991 - 7/25/2007 > >

18 years, 8 months

1
0
0 0

Almost OT: Pushbutton switch latching

by ian_primus＠yahoo.com

This should be a much simpler problem than I'm making it, but at the moment my brain doesn't want to come up with a solution. Picture this - a number of switches, say, eight. Momentary contact, normally open switches. And then eight outputs, one for each switch, TTL level. I want to be able to push one switch and bring it's corresponding output high, and have it stay high even when the switch is released. But, making this more complicated, I only want to be able to allow one switch to be active at a time. So, say switch four is pressed, output four is high. Then, switch one is pressed, and output four goes low, and output 1 goes high. Timing is not critical. I know this should be a simple array of flip flops, in some fashion, but at the moment, the solution eludes me. I feel like there is probably even a single/two chip solution to this. Now, I know that this is probably off-topic, but I'd be using this in on-topic hardware... -Ian

18 years, 8 months

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