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Inquiry about Classic Computers Collectors List

by ReCarDeaux＠aol.com

To Whom It May Concern:

22 years, 12 months

dnd

by carlin＠nauticom.net

Hello: I have been searching for the source code to DND for quite a long time now, and I ran across this post you made at some time in the past. Would you happen to have worked out the details in order to distribute the source code? I used to play this game in college many years ago, and it would mean quite a lot to me to get it up and running again. Thanks for any help that you can offer, Ken Carlin >From what I've read, banned inside of DEC is the best description :^) It >uses creatures and spells straight from D&D. Yep, I know exactly which one you speak of... I have the sources for the pascal version of the game, along with the data files, preserved for almost 20 years. I have ported the game to C using curses (actually, it was mostly a brute-force translation from the pascal) and have it running at least as well as the original pascal version (which was incomplete) at home on my Alpha PWS running Linux. I've been in contact with one of the people who was responsible for writing the pascal version, and am trying to get ahold of all the others so that I can figure out how to write up a 'copyright' page with proper attributions. >Basically all I know is what's written up at the following webpage: >http://www.io.com/~adastra/rancourt/dnd/ >It was written by Daniel Lawrence, started on the PDP-10, was ported to >RSTS/E part way through, and after that ported to VAX/VMS. I played it on RSTS/E when I was working at Parker St (DEC) in Maynard back in 1977. Actually, the pascal version was also built on RSTS using, I believe, the OMSI compiler, and ran on RT-11. Dan has apparently given permission for any and all versions of the game to exist with his blessing, but since the source I have had a copyright which is problematic (since it doesn't mention him), I have to try to do the right thing. >I grabbed the source off of the web page above, and it almost works. In >fact it might work, IF, I could figure out exactly how to build it. BTW, >the "TOPS-20" executable, looks to be a VMS V1.0 executable. If/when I can resolve the issues of attribution, I'd love to make it available... should I even bother with sourceforge? :-) Megan Gentry Former RT-11 Developer +--------------------------------+-------------------------------------+ | Megan Gentry, EMT/B, PP-ASEL | email: gentry at zk3.dec.com (work) | | Unix Support Engineering Group | mbg at world.std.com (home) | | Hewlett Packard | (s/ at /@/) | | 110 Spitbrook Rd. ZK03-2/T43 | URL: http://world.std.com/~mbg/ | | Nashua, NH 03062 | "pdp-11 programmer - some assembler | | (603) 884 1055 (DEC '77-'98) | required." - mbg KB1FCA |

22 years, 12 months

286SLT powerconfig

by metallicaman1234＠earthlink.net

what is the pin input power configuration of the 286SLT laptop and how many volts/amps is it. Also what about the battery pin config and its voltages?

22 years, 12 months

Where can one find 2.5 inch floppy disks, and other odd

by lgwalker＠mts.net

A reply to an old thread, but since I'm no longer subscribed to the list, but occasionally monitoring it, understandable. I have an old Roland PR100 sequencer. It and some other audio equipment (Akai 612 ?) as well as a Smith- Corona word processor used a 2.8 Quick Disk (flippy). I found a company that still sells the disks: http://www.esticortland.com Part #061838 but not cheap at $12.25 Lawrence ------- End of forwarded message ------- lgwalker@ mts.net

22 years, 12 months

Significance of an Apple II w/ raised power light?

by nickmiller＠charter.net

Hello, I have an original Apple II with a keyboard power on light that is raised above the case and sits in green piece of plastic. I've seen this style of Apple II in old advertisements but have not been able to find out the significance of this variant if there is one. I'm finally getting around to working on my website again and would like to address this feature, any comments would be appreciated. Thanks, Nick

22 years, 12 months

Vintage Computer Message Board

by classiccmp＠vintage-computer.com

Hello, I would like to announce a new message board that I have created in support of our community. During the past couple of years I?ve been participating as a member of this mailing list as well as several related ones. I have made a few observations that I felt needed addressing including: - the need for a better way to advertise items or help (wanted or offered) - the ability to support off topic conversations along with on- topic ones without burdening those not interested in one or the other - the ability to easily search archives for topics of interest - the ability to keep ?threads? of discussion together - the ability to categorize these threads for easier research With the above in mind I decided to experiment with a web based bulletin board (a long way from my days with RBBS and WWIV). Over the past month or so I have changed my web hosting service for www.vintage- computer.com in order to work with a hosting company that could support the new forum I was considering. Over this past weekend I finished the initial phases of moving my site and configuring the boards. The result is now available for use at www.vintage-computer.com/vcforum. A link is also available from my www.vintage-computer.com front page. Since my web hosting has been recently moved the new DNS information may not have completely propagated yet. If you get an error trying to access the above address or if the message board link from my home page refers you to an ezBoard page, please try back a little later. There are two things that I would like to stress about the new forums. First, I don?t envision them as a threat to this mailing list or the community that supports it. I see it as another tool in our toolbox (or toy in our toy chest) to enhance our enjoyment of our hobby. Second, although I set up these forums I consider them to be ?ours? in as broad a sense as that is possible. I am not only willing, but anxious to have others participate in these forums as administrators, moderators and contributors. Volunteers are welcome and operators are standing by! Hopefully if you are reading this you will see your way clear to popping over for a visit and supporting this effort with whatever you are willing to offer, be that participation, suggestions or criticism. Again, this is our community and I will do my best to make these forums reflect that. Thank you and best regards, Erik S. Klein www.vintage-computer.com

22 years, 12 months

77/68 computer (was Seeking good home...)

by Paul.HILLS＠landisgyr.com

Andy, I guess the Electronics and Computing Monthly magazine and Stirling Microsystems must have based the design on the ACC one. The ECM design was on 8" square boards too, single sided tracks (you had to run loads of wire straps!). I still have all the documentation for it, paper-based at the moment. There was a choice between a 40x24 monochrome display board implemented entirely in 4000-series CMOS (which I built), or a newer colour board with 64K RAM and a Thomson EF9365 Graphic Display Processor. I didn't build that since the cost of 64k RAM in 1982 was prohibitive! That processor could draw at 1 million pixels per second - impressive for 1982. Some of the documentation is published by Newbear (Newbury Electronics), and some by Stirling. One day I'll get around to scanning all the docs in for general availibility. paul -----Original Message----- From: Andy Holt [mailto:andyh@andyh-rayleigh.freeserve.co.uk] Sent: 19 April 2003 20:40 To: cctalk(a)classiccmp.org Subject: RE: Seeking good home(s) for old hardware [UK] > Getting on 20 years ago I built a 6809 based computer from a > series running in the UK magazine "Electronics & Computing > Monthly", called the 77/68 system. This was based on the SWTP > stuff but was marketed through a company called Stirling > Microsystems in Baker Street, London. Does anyone else here > remember that system? ... As I remember it, the 77/68 was published in the ACC newsletter (not in E&CM) - the original was a rather neat design by Mike Lord on 8" square PCBs. I built a seriously extended one of these (which eventually "fissioned" into two complete systems - connected by a homebrew network that was a sort of very cheap slow ethernet). Some boards were from the original design - others I designed and implemented myself ... most notably including a 6809 board (the original was a 6800) with the only technical data being a pin-out and some other vague descriptions in a Byte article. It was a couple of years of successful use before I discovered that I was feeding the clock in through the "wrong" pin! Amongst the peripherals that this system acquired was a large Calcomp plotter surplus from the University mainframe. Unfortunately most of the hardware and documents have now been recycled or worse. Andy

22 years, 12 months

HP9915

by ard＠p850ug1.demon.co.uk

I've recently had an HP9915 on the bench. This, as many of you are aware, is related to the HP85, but it's in a metal case with no printer, keyboard (although there is a keyboard connector on the back) or monitor (again, there's a composite video output on the back). Some details of the insides : Almost all the HP ICs are the same as those in the HP85 (CPU, CRT controller, RAM controller, Keyboard controller, ROMs, I/O buffer, even the printer controller is there). Much of the rest of the circuitry is similar to that in the HP85 (PSU, etc). There's an extra 8048 microcontroller that handles the power-on reset, self-test and autostart keys, and the front panel LEDs. It connects to the HP CPU via an I/O Translator IC, which is the same as the one used in the HP85 interface modules. Also linked to this microcontroller is a PCB that can contain up to 8 2716 (or 2732 if you rearrange the links) EPROMs. I have no idea (yet) how to format data to put in said EPROMs. The large board in the bottom of the case contains the PSU, and much of the logic circuitry. There are 6 'option ROM' spaces at the back of this board, identical to those in an HP85 ROM drawer. The PSU provides the same voltages, in much the same way, as the HP85 CPU. The output of the transformer is rectified and fed t oa switching converter (U30, 3524 is the controller IC) to provide +12V, -5V and -12V. This poweres a second switching converter to provide +5V. The +6V is obtained by a linear regulator. There is a crowbar (Q4) which will short out the input to the first PSU if the +12V line rises too high. This will then blow the mains fuse (something to check if the mains fuse blows at switch-on -- maybe Q5, PIC645, the first chopper is shorted). Another PCB plugged into the left edge of the main PCB contains the video RAM, printer chip (used here for the timers, I suspect), buffers/clamp networks for the keyboard and control connectors, a state machine to generate the video sync signals, and the composite video mixer. It has been suggested this is the 'operator interface' mentioned on the options box on the back, but I think not. I think this must be a standard part of the machine, and that the 'operator interface' is the keypad on the front. Talking of the keypad, the top 4 keys are connected as the k1-k4 keys of the HP85 keyboard. The blue key is connected as the shift key. On the back of the machine (actually on the vertically-mounted PCB that I mentioned a couple of paragraphs back) are 2 D connectors. The pinouts seem to be : Keyboard (DB25) 1 : chassis ground 2 : R0X (this is Row 0 output, buffered) 3 : R1X 4 : R2X 5 : R3X 6 : R4X 7 : Logic ground 8 : Logic Ground 9 : R5X 10 : R6X 11 : R7X 12 : R8X 13 : R9X 14 : C0X (Column 0 input, buffered) 15 : C1X 16 : C2X 17 : C3X 18 : C4X 19 : C5X 20 : C6X 21 : C7X 22 : KSX/ (Shift key, connect to logic ground to shift) 23 : KCX/ (Control key, ditto) 24 : KCLX/ (Caps lock key, ditto) 25 : SpkrX (Speaker output, return to logic ground) Control connector, DA15 1 : LED0X (High if top LED on frontpanel is on) 2 : LED1X 3 : LED2X 4 : LED3X 5 : LED4X 6 : LED5X 7 : LED6X 8 : LED7X 9 : RunX/ (RUN LED output) 10 : TestX (selftest LED output) 11 ; PWOX (Power OK output) 12 : Logic ground 13 : KeyStartX/ (ground for autostart key) 14 : KeyStX/ (ground for self test key) 15 : Chassis ground. The keyboard matrix would appear to be the same as that in the HP85 OK< a couple of questions 1) What is the impedance of the speaker in the keyboard (presumably between SpkrX and logic ground? 80 ohms? 2) What is the OD of the tape drive roller? Mine has decayed (what a suprise), and I need to rebuild it. It should be the same as the roller in the HP85, the HP9825, HP9815, etc.... -tony

22 years, 12 months

Soroc IQ120 Chip Problem

by marvin＠rain.org

I finally started digging in to find out what was wrong with a couple Soroc IQ120s. The first one was easy; just a memory chip (2102) that went bad. The second one is a bit tougher. I *think* I have the problem narrowed down to a Signetics 82S201 PLA, and therein lies the problem. Is there a replacement chip available, and is the coding of the chip available? If the coding is not availble, can I just go through a counter on the input and record the output states to come up with the chip programming? Needless to say, I am not real familiar with these devices :). There are two of these devices in parallel, and when I pull out the supected bad one (one makes no difference, pulling the other one starts the screen display again), the screen starts to work again. My suspicion is that the two are in parallel to increase the drive to the other chips. There are probably more problems since I don't hear the beep when the unit is turned on. The keyboard unit has already been checked out on the working Soroc. Any thoughts or comments?

23 years

Northgate OmniKey Ultra

by fmc＠reanimators.org

David Holland <dholland(a)woh.rr.com> wrote: > I've had it for about a week now, and just can't get used to funky > arrangement of the arrow keys in the middle, and the F keys on the left > just throws my Unreal Tournament gaming off. So we know it's one of the sort with the Omni key instead of an inverted-T layout. If it's an Ultra, it should also have the function keys across the top. > Anyways, I gather these things were something of a 'gotta have it' > keyboard at one time, and were bloody expensive. Not that bad. In the mid-1990s you could get them for about $70, which seems expensive for a keyboard, but for those of us who really wanted the control key to be to the left of A and didn't want to have to fuss with driver software to make it happen, it was well worth it. If you want expensive, go check out the Avant Stellar! That is reportedly the modern Northgate OmniKey, and it sells for about $150. > I gather it might of came with some extra keycaps when it was new, so > you could move around control/shift. I do not have those. So, some questions to help folks ID what you've got. Is the control key to the left of A? Where are the switches? Poking out the back, or hidden under the "OmniKey" flip-top lid, or not present at all (flip the lid up, see nothing)? Not present at all means it is a late-model programmable keyboard. They had firmware bugs, and the "fix" was "remove the EEPROM that holds the key remappings". > Anyone want it? (I think this is at least on-topic) Somebody better! -Frank McConnell

23 years

HP's Amigo Protocol, HFS

by peterbrown10＠hotmail.com

Hi Joe, The drive is a 9134XV - serial number begins with 23 so I guess that it would be from around 1983. If I look at the drive with an HP 9000 332 it sees an HFS partition - with basic 6.0 binaries :). When I ask the drive to identify itself it returns a pair of bytes that I don't recognise (1 and 15 from memory but I could be wrong). This pair of bytes is not the same as the pair that would be returned by a CS80 drive. I managed to check the reader software with a pair of 9133 drives, a 9134 drive (which fails) and a 7907 drive (this identifies itself correctly but appears to have been wiped of data at some time). I have some other software recorded on 7906 removable cartridges - does anyone know if an HPIB version of this drive was made? - I think that the model number may be 7906H but I have no further information. Does anyone have a 7906H tht they don't need? Cheers Peter Brown _________________________________________________________________ On the move? Get Hotmail on your mobile phone http://www.msn.co.uk/mobile

23 years

VCF Europa Live

by vcf＠siconic.com

I fixed the VCF Europa Live pages from the vintage.org server. To see live pictures from VCF Europa 4.0, go here: http://www.vintage.org/2003/europa/ ...and click on "VCF Life". Look for the guy in the Blue Shirt and that will be Hans (Hansi Smurf). -- Sellam Ismail Vintage Computer Festival ------------------------------------------------------------------------------ International Man of Intrigue and Danger http://www.vintage.org * Old computing resources for business and academia at www.VintageTech.com *

23 years

HP's Amigo Protocall & HP IPC

by rigdonj＠cfl.rr.com

Yesterday I was cleaning out and putting some excess HP manuals on E-bay. One of the books that I found, HP-UX Concepts and Tutorials - Device I/O and User Interfacing, looked interesting but was still sealed so I listed it without opening it to see exactly what it covered. (I'm not real big on HP-UX). Today I found another copy of the same manual. It was alreadu opened so I've been reading through it. First, it DOES cover the HP IPC (Intergral Personal Computer) along with the HP 9000 Series 200/300, Series 500 and Series 800 computers. Each function that only applies to certain systems is flagged and there are appendices for the IPC and each of the other series that list and describe any peculiarities of that implementation. BUT what was even more surprising is that it states that many of the HP printers use the Amigo protocall! For the ones of you that aren't familiar with HPs that protocall is used for low end disk drives. This is the first time that I've heard that was also used for printers. Besides that statement it also has a "non-trivel" programming example of an "HP-IB driver that uses the Device I/O Library subroutines to drive various models of the HP Amigo protocall HP-IB printers". This might be a good starting point for anyone that wants to write and Amigo driver to talk to disk drives. Are you listening, Sergio and Peter? This book is definitely a keeper! It describes the HP-IB and GPIO interfaces for the various systems in detail including their status and control registers. It then describes how to use the DIL (Device I/O Library) included with HP-UX to set, read and control the interfaces and how to link calls to the DIL from Fortran, Pascal and Assembly language programs. It looks like a great source of info for anyone that wants to write their own device drivers or wants low level control of HP-IB and GPIO interfaces under HP-UX. I'm keeping this copy but I have another one that's already on E-bay. I know this sounds like a shameless plug but it's not. I'm just really impressed with this book. Joe

23 years

MicroVAX4000/505A drive sleds

by ClassicComputers＠bouncy-castle.demon.co.uk

Just acquired a VAX 4000/505A (thanks Paul!) with no disks installed - anyone got the details for adding a raw DSSI disk to one of these things ; the chasis has a drive backplane at the top with 4 edge connectors, into which a drive sled of some form slots in. I need to knock up whatever is on the sleds, drive LEDs & switches. Unless anyone has some excess sleds that I could liberate?... Ohhh, wonder if the MDS pils of docs has any details on this - off to look now :) ta greg

23 years

VCF Europa 4.0

by vcf＠siconic.com

This weekend is VCF Europa 4.0 in Muenchen, Deustchland! Complete information is on the VCF Europa website: http://www.vcfe.de I look forward to reports from those that make it since I won't be present this year :( -- Sellam Ismail Vintage Computer Festival ------------------------------------------------------------------------------ International Man of Intrigue and Danger http://www.vintage.org * Old computing resources for business and academia at www.VintageTech.com *

23 years

Heathkit EC-1

by dwightk.elvey＠amd.com

>From: "Doug Coward" <mranalog(a)attbi.com> > > Ethan wrote: >> How does a resistive sheet computer work? > > I wrote: >> Resistive sheets belong to a category of analog >> computing called network analyzers. > > Oops, I need to correct this. > Resistive sheets belong to a category of analog Hi This is the place to describe my method of finding shorts on power planes. This is very much like the resistive sheet methods. You place a power supply across one of the two planes that has shorts between them, such that about one or two amps is flowing in current limit. You place one lead of a volt meter on the opposite plane and then probe with the other lead on the plane with the current flowing across it. You find a line where the meter reads zero. Now, move the power leads to an orthogonal corners. Again fine the line of zero volts. Where the two lines cross, you'll find the short. There are variations of this method for finding shorts between traces and even multiple shorts. Dwight

23 years

Heathkit EC-1

by dwightk.elvey＠amd.com

>X-Server-Uuid: 262C4BA7-64EE-471D-8B02-117625D613AB >X-Authentication-Warning: huey.classiccmp.org: mailnull set sender to cctalk-admin using -f >From: "Doug Coward" <mranalog(a)attbi.com> >X-Accept-Language: en >MIME-Version: 1.0 >To: cctalk(a)classiccmp.org >Subject: Re: Heathkit EC-1 >X-BeenThere: cctalk(a)classiccmp.org >X-Mailman-Version: 2.0.10 >List-Unsubscribe: <http://www.classiccmp.org/mailman/listinfo/cctalk>, <mailto:cctalk-request@classiccmp.org?subject=unsubscribe> >List-Id: General Discussion: On-Topic and Off-Topic Posts <cctalk.classiccmp.org> >List-Post: <mailto:cctalk@classiccmp.org> >List-Help: <mailto:cctalk-request@classiccmp.org?subject=help> >List-Subscribe: <http://www.classiccmp.org/mailman/listinfo/cctalk>, <mailto:cctalk-request@classiccmp.org?subject=subscribe> >List-Archive: <http://www.classiccmp.org/pipermail/cctalk/> >X-Original-Date: Fri, 02 May 2003 11:59:27 -0700 >Date: Fri, 02 May 2003 11:59:27 -0700 >X-WSS-ID: 12AC63976885576-01-01 >Content-Transfer-Encoding: 8bit > > Ethan wrote: >> How does a resistive sheet computer work? > > Just a quick note for now. > Resistive sheets belong to a category of analog >computing called network analyzers. > >> In the same vein (pun intended)... how would fluidic computers >> stack up? Digital? Analog? Mixed? > > Fluidics (or fluid logic) can have both analog >and digital processes. You can perform boolean >operations, but you also can have fluid amplifers. Hi An interesting side note. The power steering of your auto is an example of an analog fluid amplifier. Dwight > --Doug >========================================= >Doug Coward >@ home in Poulsbo, WA > >Analog Computer Online Museum and History Center >http://dcoward.best.vwh.net/analog >=========================================

23 years

Northgate OmniKey Ultra

by dholland＠woh.rr.com

Howdy all, I stumbled across a Northgate Omnikey Ultra (not UltraPlus) keyboard in the local thrift store, and picked it up for 5$. (It had a nice feel, kinda PS/2'ish, and no stupid windows, or various other internet/volume controls/etc keys.) I've had it for about a week now, and just can't get used to funky arrangement of the arrow keys in the middle, and the F keys on the left just throws my Unreal Tournament gaming off. (See http://www.northgate-keyboard-repair.com for some piccy's) Anyways, I gather these things were something of a 'gotta have it' keyboard at one time, and were bloody expensive. Thought I'd offer it up here, for 5$ + shipping before it goes downstairs in the basement to collect dust. One thing to note, is its got one of the AT style connectors in back, so you'll need an adapter if your going to plug it into a PS/2 style connector. (No, you can't have the one I was using) Visually, its pretty clean, there's a little green stuff on the bottom where I attacked (mostly ineffectively) some sticky stuff w/ a scrubbing sponge, but the top is (imho) nice and clean. I think all the keys work, however, there might be a few F keys I didn't hit the week I was using it. I gather it might of came with some extra keycaps when it was new, so you could move around control/shift. I do not have those. Anyways, enough disclaimers, Anyone want it? (I think this is at least on-topic) David

23 years

Analog auto systems (was: Heathkit EC-1

by dwightk.elvey＠amd.com

>From: "Fred Cisin (XenoSoft)" <cisin(a)xenosoft.com> > >> > > I don't think _my_ auto (1968 Beetle) is an example of that. :-) >> > Well, now - not so fast! While your Bug may not have power steering, >> > if it's got an automatic transmission... >> Nope... 4-speed manual. There was this thing called an "auto-stick", >> but that was a servo-operated clutch (and an ordinary manual transmission) >> that engaged when you began to move the stick. You still shifted, but >> you didn't clutch. > >I don't think that I would call a torque converter a "servo". > Hi I put a brake servo on my '53 power wagon. That is gone now. The storm this last winter blew over a 147 foot Douglas Fir onto it. It push all 4 tires into the ground, down to the axles, and the axles to the frame. I think this is when the body finally gave. Dwight

23 years

Heathkit EC-1

by dwightk.elvey＠amd.com

>From: "Ethan Dicks" <erd_6502(a)yahoo.com> > >--- "Dwight K. Elvey" <dwightk.elvey(a)amd.com> wrote: >> Hi >> An interesting side note. The power steering of your >> auto is an example of an analog fluid amplifier. >> Dwight > >I don't think _my_ auto (1968 Beetle) is an example of that. :-) > >-ethan Hi Actually, now that you mention it, my '68 Fiat 124 Spider isn't either but it does have a vacuum booster on the master cylender. I guess well have to buy newer examples of analog amplifiers. Dwight

23 years

Looking for a 11/44 in denver area / colorado

by emu＠ecubics.com

Hi, Anybody out in colorado with a "spare" 11/44 ? Or even just a power supply for a 11/44 ? cheers & thanks

23 years

Neat find (in my own junk bin!) - NS 8073

by erd_6502＠yahoo.com

I was collecting all of my hex LED displays into one place so I can test them before embarking on a new 1802 project. I even dug into my old box of spare Elf parts and pulled out a small board with four TIL311 displays attached to a small microcontroller board - some kind of monitor/indicator given to me by the brother of the guy that got me into the 1802 as a kid. He had given it to me to harvest the TIL displays. I finally *looked* at the attached board to see what was on it - an NS 8073! I used to have access to an RB5X robot when I was a volunteer at the local science museum in High School - same chip - the hot-item-for-a-brief-moment microcontroller with embedded Tiny Basic. Now, rather than harvest the parts, I'm very tempted to reverse-engineer the schematic of the little board to see what it does. Looks like there's a small bipolar PROM, a 6116 SRAM, one or two TTL chips, and the TIL311s driven by the output pins of the 8073. The whole thing is only a few square inches. The funny thing is that I'd recently picked up a few 8073s from ePay to play with. I was planning on hooking them up to some 8031-based 8-line LCD displays I got for a few bucks each (originally out of some flavor of AT&T office phone, IIRC). Sort of the Classic Attraction principle in reverse - new toys attracting alike items >from the recesses of the junk box rather than the normal way 'round. Has anyone else played with the 8073 (in an RB5X or not)? If they hadn't been so pricey 20 years ago, I might have gotten one to experiment with back then. -ethan The New Yahoo! Search - Faster. Easier. Bingo. http://search.yahoo.com

23 years

Heathkit EC-1

by mranalog＠attbi.com

Ethan wrote: > How does a resistive sheet computer work? I wrote: > Resistive sheets belong to a category of analog > computing called network analyzers. Oops, I need to correct this. Resistive sheets belong to a category of analog computing called passive element computers in which network analyzers are probably the biggest and most well known examples. But it also includes * conductive sheets * electrolytic tanks - create 3 dimensional simulations * resistor networks * pin and rod systems * resistor and capacitor network Passive element computers normally models a physical system using only passive R-L-C components, and solve equations in which dimensions in space are the independent variables, rather than time. Applications for passive element computers include things like the simulation of * reception patterns of a receiving antenna * temperture, and pressure flow in a nozzle * diffusion of material at a transistor junction Here is an example: You solder together a large two dimensional matrix of resistors (all the same value). At each node where the resistors are soldered together you solder a capacitor connected to ground. You then apply a voltage to one corner of this resistor and capacitor network. As the current flows through the network it begins to charge the capacitors. You now have a computer that simulates the heat flow across a metal plate the size of your matrix, both over distance and over time. Without the capacitors you are simulating only over distance. A resistive sheet is a resistor matrix with a very fine mesh. The finer the mesh, the better the simulation. "Rubber-sheet computers have been used extensively to study the trajectories of electrons and gas ions in vacuum and gas tubes" -Doug ========================================= Doug Coward @ home in Poulsbo, WA Analog Computer Online Museum and History Center http://dcoward.best.vwh.net/analog =========================================

23 years

HP Amigo command set and HFS disk format

by peterbrown10＠hotmail.com

Hi All, Looks as though the CS80 / LIF part of my HPIB disk reader/writer is working OK now - thanks to those who gave me pointers. I've come across another HPIB hard disk that that uses the Amigo command set (- I think) and contains data in HFS format. Does anyone have full documentation for these two standards in .pdf format? Cheers Peter Brown _________________________________________________________________ On the move? Get Hotmail on your mobile phone http://www.msn.co.uk/mobile

23 years

256x4 80NS or faster

by anheier＠owt.com

I have a fair quantity of the following: P21256-12 MCM6256BP12 Lh21256-12 MTC4c1024-8 KM41C1000BP-8 thanks Norm snip: >Date: Tue, 29 Apr 2003 11:37:28 -0700 >To: classiccmp(a)classiccmp.org >From: Geoff Reed <geoffr(a)zipcon.net> >Subject: 256x4 80NS or faster >Reply-To: cctalk(a)classiccmp.org >anyone have any of these floating around? I can't believe I gave 'em all >away and now I need to populate a laserjet IIID memory board :(

23 years

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1999

1998

1997

test-drb