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

by michael.99.thompson＠gmail.com

> > From: Jerry Wright > Sent: Friday, February 06, 2015 8:54 PM > Subject: RA-81 issues > > I have a rack full of RA81's, all Pass Rom base self test. If I try to > spin > up one of the drives, It will start to spin up and then just stop. There > are > no front panel lights that come on or codes on the terminal screen. all 3 > drives do the same. > > These are not connected to a controller, and the manual does not say this > is need. > > The forth one has no drive and the motor seems to turn hard, is there a > brake > on the motor ??? > > - what I'm I missing here > Thanks Jerry > I have seen two common problems problems with RA-81 drives. Failure of the motor start capacitor, and failure of the optical sensor on the bottom of the HDA for spindle speed. With both failures the drive will start to spin-up, and then spin-down. You can connect a serial terminal emulator to the DB25 diag connector. Then you can run internal diagnostics and get the fault codes. The RICM has several RA-81 drives, all with failed optical sensors. -- Michael Thompson

11 years, 4 months

1
0
0 0

11/23 clock issue

by jnc＠mercury.lcs.mit.edu

> From: Brent Hilpert >> Well, try removing W1 to isolate the output of the xtal oscillator E15 >> from inverter input pin E4.4. Sigh, the crystal output is dead as a doornail. Total flat-line. Guess I'm going to have to find a new one... I actually think there's an open in there, because the input to the buffer inverter stays at +2V, whether the crystal is connected or not. If there was some sort of internal short in the crystal taking its output to ground, I'd have expected it to pull the inverter's input down. > TP4 looks to be an 'input' test point, rather than an output. The > pull-down resistor value (150 or 180 ohms) has been selected such that > it is low enough to allow enough current to flow through the tri-state > control input E4.1 to pull it low normally, but high enough to allow > one to connect TP4 high, to enter tri-state Ah, got it. (I tended to assume test points were outputs, but I need to remember that they may be inputs.) > What the point of going to tri-state is, is not clear, considering that > W1 is there for an external clock. A conjecture is there may have been > some external test fixture that tri-stated it for some sort of > synchronous single-step clocking. Yeah, but couldn't they have lifted the W1 jumper, and fed their test clock in that way? Eh, not important. > Could also check the V reading on the open E4.4 input. See above - +2V is a floating TTL input, ISTR? > From: Holm Tiffe > Hmm, may be since his hints are standard debugging technique and you > aren't really familiar with debugging?? I cheerfully admit to being primarily a software person. But I have been debugging broken hardware off and on for 30+ years - although not as a principal occupation, of course. I think it's more just that my mind does not do hardware intuitively (the more-so, the further one gets from the ideal - aka digital at the design level - to real hardware) - I have to think about it. > You don't ned no pullup for +5. All open TTL inputs are reading High > w/o any pullup. That's why all those boards use pullups on unused inputs that need to be 1, right? :-) But you're probably correct for a quick test. Noel

11 years, 4 months

4
3
0 0

seeking quality tape recorder

by dave＠661.org

I'm looking for a decent quality portable tape recorder. I do want recording ability so I can make new tapes for my C64 among other purposes. I was about to purchase an Ion Tape Express Plus, but was told by Silent700 in #classiccmp that his imposes an abnoxious throbbing noise to the audio. Does anyone have any different experiences with that unit? Can you recommend something good other than the Ion one? -- David Griffith dave at 661.org A: Because it fouls the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail?

11 years, 4 months

8
9
0 0

Stupid AC wiring question (220-ish Volts...)

by jnc＠mercury.lcs.mit.edu

> From: Josh Dersch > Luckily heavy items can be wheeled on a hand-cart around to the back of > the house, where there's direct access to the basement; no tricky > stairs to deal with. O lucky man! My basement is only stairs-accessible (although one of them is an outside stairs, which is a big help), which led to an extremely annoying incident recently. (This has nothing to do with wiring, but your comment poked a hot-button...) I already had one 11/84, which was donated to me by a fellow aficionado of PDP-11's out in Wisconsin. When I got it here, I was trying to work out how to get it all (CPU cabinet, TU80 cabinet, RA81 cabinet [no drives], and 2 RA81's [separate]) into the basement (the only feasible place to put it in our establishment). I wound up building a ramp out of 2x10's on the outside stairs, and using a block+tackle to lower the units down that into the basement. Worked pretty well, actually - got the whole works down by myself in a couple of hours. So I got another 11/84 system (yeah, yeah, I know) which was in Fornicalia, and had to have it shipped. I originally tried to ship it freight (hey, the units are on wheels, and I didn't care if it got dinged a bit through not being packaged), but when they found out it wasn't palletized, I had to go 'white glove' (at twice the cost). But the good part was 'at least' with WG you get 'inside delivery'. So I'm figuring, good, they'll help me get it into the basement. Nothing doing. I showed them the units in the basement (so they'd know I had experience doing it), they looked at the ramp, and they called their company and then flat-out refused to have anything to do with the process. They claimed they thought it was 'dangerous'. I suspect their real motivation was i) it was raining lightly (which is another irritating thing, they were orignally scheduled to deliver on a day when it was supposed to be good weather, and they begged to move the delivery up, and I told them about the weather, but they were insistent, so I agreed - big mistake, I should have dug in my heels), and ii) they were in a hurry (see previous about wanting to deliver a day early) and wanted to hit the road ASAP. So anyway, we stuck it all in the garage to wait for a day it wasn't raining (hey, if I had to do it all myself, why do it in the rain?), and then my wife and I (she's 4' 10", and all of like 90 lbs) got it into the basement in a couple of hours, no problem. But two big, burly moving guys (I'm 6'0", 200 lbs, and they were a lot bigger than me) thought it was too much for them. To add final insult to injury, the moving company refused to offer any partial refund for not providing the 'inside delivery' they had been paid (a lot!) for! In addition to all the above, it took them 6 weeks to get the stuff here from California. Now, admittedly, Christmas and New Year's were in there, but... Anyway, I would highly recommend having nothing to do with this company; it was an outfit called UKAY. I've dealt with a number of crappy shippers, but these guys were The Shipping Company From Hell. Tell everyone you know about them. Noel

11 years, 4 months

1
0
0 0

It's time to restore the 11/45 - progress!

by jacob.ritorto＠gmail.com

Hey everyone, making some progress here -- thanks for all the tips so far! Most of the power regulators are fine, but both H745 regulators seem to be toast. Only getting -1.2 volts; should be -15 and they squeal angrily when I turn the pot. The surplus shops seem to want $200 for one, so that's not an option for me. How does one repair such a beast? thx jake P.S. Also, the main H742s are sagging just a little, but I didn't see an adjustment on them to bring them up. Anyone know where to look?

11 years, 4 months

7
12
0 0

11/23 clock issue

by jnc＠mercury.lcs.mit.edu

> From: Tothwolf >> Sigh, the crystal output is dead as a doornail. Total flat-line. Guess >> I'm going to have to find a new one... > Does it have to be exactly 13MHz for the system to function correctly? > I have some Fox brand 13.824MHz oscillators Actually, they are exactly 13.824MHz on the 11/23, too. Must be a standard speed... > in my parts cabinets that were leftovers from something back in the mid > 90s (probably modem R&D). Oh, this may be totally fantastic. I spent a chunk of time today looking for a replacement, and so far, no luck. So you may really be a life-saver. A generic search for 13.824MHz crystals turned up a whole bunch of SMD parts, and a few of what I think are actual crystals (two leads), but none of those self-contained DIP oscillator units. I have a couple of 11/23 cards, and although the DIP oscillators on them are >from a number of different manufacturers, they all have the same number on them: "18-12131-00", which must be some standard part number. So I tried looking for that, and all I found were a couple of those part-finder services. So, just for grins, I asked three of them for quotes. Only one replied, and they couldn't find them. So if you've got some of the DIP oscillator units, that'd be a life-saver. I'll contact you off-list to work out the logistics? Thanks! Noel

11 years, 4 months

2
1
0 0

Radio Shack

by marc.verdiell＠gmail.com

You are so absolutely right, you should have been their marketing director and they'd still be around. People still like to build things just the same! They completely missed the Maker movement, the computer mod stuff, the switch to the web. Also too many stores, too small. The stuff they had in there lately was an appalling mish-mash of uninteresting random stuff. No need to read the news, you could so clearly see that the company management was so totally lost and aimless by just visiting a store. Here in the Valley, Fry's Electronics took over, and then made it so much better. Fry's is where you stop at lunch time, for amateur or professional stuff alike, and get an instant replacement for your fried LM7805. It also keeps our company electronics lab and fab and IT alive. And you can get an espresso at the same time, and a pack of sugar loaded cookies if you are a late night programmer. And a concert on a full size Steinway while you are picking up your capacitor. Let's not forget the best of it, being chased around by the totally incompetent sales person that will convince you that SATA and USB are one and the same thing. Trying to lose him by walking progressively faster. Man, they can walk fast too, these are trained professionals. And for the grand finale, being stripped searched going out the door. How is that for the ultimate nerd store experience! Love it all. The Fry brothers are geniuses. Marc >fahimi wrote: > >RadioShack had it essentially right in the 2014 Super Bowl commercial - the 80s called and they did want their store back. What they screwed up was thinking that meant >the old store had to go and be replaced with the current monstrosity. >RadioShack should have brought back the store of the 1980s and updated it items like cheap cables, Raspberry Pi kits, etc. I.E. hobbyist and do it yourself stuff. Yes, they >still would have to close a number of locations (do you really need a ratshack on every corner?) but what would have been left behind would have thrived...

11 years, 4 months

7
6
0 0

Xerox 4050/4090 print controllers

by microfilm＠microfilm.kscoxmail.com

I'm doing some cleaning and purging around my shop, and I have a collection of Xerox 4050 and 4090 printers and parts, plus the controllers for these beasts. Is there any interest at all in this equipment? I have to get rid of it, soon, but don't want to simply scrap it if there's someone interested in such niche equipment. The CPU itself is a DJC11, 11/70 on a chip. Other peripherals include a Bus & Tag online interface boardset, graphics processor options (I have one seat of each of the two different options that exist, but the system can only handle one at a time), memory boards, FDDC2 floppy controller (contains an Intel 8086, plus a set of Western Digital chips), a board dedicated to print controller to print engine communications, a hard disk interface (up to four MFM disks, in pairs. Originally had two Fujitsu 56MB disks, later replaced with Seagate drives). The terminal for the system is either a Lear-Siegler ADM-3A, or a Link Technologies terminal in ADM-3A mode, both with minor keyboard modifications. (I have several of these terminals on hand.) Barring interest here, the whole lot will be salvaged and the chips sold off. Keep in mind, this stuff is big. The individual interface boards are slightly larger than a hex-height Unibus board. The card cage for the system is about 24" wide, 18" deep, and 30" tall. The complete controller cabinet, with 9T tape drive, is over 5 feet tall, 3 feet wide, and 2 feet deep. I also have other equipment and supplies (8" and 5.25" floppies, new in sealed packages, for example) to move. Everything is located in Wichita, Kansas. --Shaun Microfilm Services, Inc.

11 years, 4 months

4
3
0 0

What is this Concurrent Computer Corporation machine?

by pontus＠update.uu.se

Hi My employer has over the years ported our main product to more platforms than I can count. I took inventory of our storage the other day and one machine has left me clueless: The Concurrent Computer Corporation machine: http://www.update.uu.se/~pontus/slask/jobb_vind/DSC_0081.thumb.jpg http://www.update.uu.se/~pontus/slask/jobb_vind/DSC_0082.thumb.jpg http://www.update.uu.se/~pontus/slask/jobb_vind/DSC_0083.thumb.jpg As you see it is one rack with a medium sized computer in it. From the internet and co-workers I've learned that it has either a MIPS or 68k processor and runs a unix version called RTU, for Real Time Unix. CCC was initially Interdata, later Perkin Elmer and then spun off into CCC. Has any cctalk-reader experience with this system? Anything would be interesting to learn. This machine might become available in one way or another later this year. And since I believe it was made in Brittain I've pondered asking TNMOC if they want it. Finally, check the content of the directory above for some more Unix history. Kind Regards, Pontus.

11 years, 4 months

1
0
0 0

Pdp11/23+ EPROM upgrade

by roeapeterson＠gmail.com

I want to update the EPROMs on my 11/23+, which currently has 2716s. I'm going to need 64k chips, and I understand 2764s won't work on this board. What are my replacement options? I have a fairly capable programmer, it can probably handle anything with 64k capacity. Thanks.

11 years, 4 months

6
13
0 0

Stupid AC wiring question (220-ish Volts...)

by derschjo＠gmail.com

I picked up a "large" machine* (for certain definitions of large) that's currently configured for 220-240V; my house at the moment lacks 220V receptacles. I was already planning to get an electrician out here to put in some beefier wiring at some point (I have a couple of machines that draw 15-20A off of 120V that I'd like to be able to run) but I wasn't yet planning on doing 220V unless I have to. (It looks like in theory it's possible to reconfigure the supply for 120V but I lack the docs to do so with any level of confidence...) I don't know if this machine works, and I'd rather not invest in 220V wiring quite yet unless it does. And, let's face it, I'm spoiled and I demand instant gratification and I'd like to know as soon as possible if this machine is a basket case or not. So: since all this stuff is in the basement, I'm just about 15 feet away from the dryer, which at first glance runs off an outlet that meets my needs. I even have a NEMA 10-30p plug here that I could wire up to the existing power cable for the computer. But looking into it I have doubts that it's actually that simple; in particular since this house was built well before 1996 and so the outlet is not grounded; there's a neutral lug and two hot lugs (I assume two 120V A/C lines out of phase?) and I'm guessing that might not sit well with the power supply in this computer. But then, I'm a rank amateur when it comes to house wiring and A/C and power supplies and all of that so I thought I'd ask the cctalk collective whether this can be made to work or if I should simply wait for a professional to take care of it... Thanks as always, Josh * An AMT DAP 610, if you must ask. It's an array processor from the late 80s, with 64x64 1-bit processors. If the machine doesn't run I'm pretty much SOL for spare parts, schematics, service manuals, or anything beyond customer-level documentation (which I've recently scanned, btw, if anyone's curious...)

11 years, 4 months

10
18
0 0

Did Dr. Marc Dean Design the IBM PC or was it Lewis Eggebrecht

by christian_liendo＠yahoo.com

Ok.. So Engadget wrote this article claiming Dr. Mark Dean was chief engineer of the 12-person team that designed the original IBM PC in the early '80s http://www.engadget.com/2015/02/06/mark-dean-pc-pioneer/ I had always thought it was Lewis Eggebrecht. I know there were three teams and one of them won and it was Eggebrecht's team. Did Dr. Marc Dean work on Eggebrecht's team or did he run one of the other ones?

11 years, 4 months

3
6
0 0

Fry's expansion? was: RE: Radio Shack

by tiggerlasv＠aim.com

On Fri Feb 6 15:09:42 CST 2015, geneb geneb at deltasoft.com wrote: > They're in Renton, WA as well. Now if they'd just keep the parts pegs filled... Yeah, that's been on ongoing issue for Fry's at all of their locations. I've been to Fry's in San Diego, Las Vegas, both Phoenix locations, Wilsonville, and of course the one closest to me in Renton. Great place if you need PC components; they have a lot of odd/unusual items that you might ordinarily only find on-line, or at PC swap-meets. You'll find some killer deals there as well. Several years ago, they were clearing out some 18-gig SCSI Cheetahs. I picked up 4 of them for $20 each. However, as mentioned by Gene, they are frequently out-of-stock on a lot of their electronic components. . . whether it is an obscure item or commonly-used components. I can never rely on finding the right value cap or resistor on their shelf. Another quirk that they have is product placement and pricing. You might find an audio adapter or cable by one manufacturer in the components section at one price, and in the audio section by a different manufacturer, at a significantly different price. I've also noticed that (at least in Renton) that their selection of generic cables has decreased, in favor of expensive brands like Monster or Belkin. Nowadays, I don't even mess with Fry's for A/V or computer cables -- I go straight to MonoPrice.com T

11 years, 4 months

1
0
0 0

Fry's expansion? was: RE: Radio Shack

by cclist＠sydex.com

On 02/06/2015 11:58 AM, Bill Sudbrink wrote: > Marc Verdiell wrote: >> Here in the Valley, Fry's Electronics took over, and then made it so >> much better. Fry's is where you stop at lunch time, for amateur or >> professional stuff alike, and get an instant replacement for your >> fried LM7805. > > A few years ago, there was a rumor that Fry's was going to expand out > of the Valley. I wonder whether that might happen now that RS is > on its way out. Where have you been the last few years? http://www.frys.com/ac/storeinfo/storelocator --Chuck

11 years, 4 months

6
7
0 0

Fry's expansion? was: RE: Radio Shack

by rickb＠bensene.com

There is a Fry's in Wilsonville, Oregon -- They've already expanded out of "the valley". -Rick > -----Original Message----- > From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Bill > Sudbrink > Sent: Friday, February 06, 2015 11:59 AM > To: 'General Discussion: On-Topic and Off-Topic Posts' > Subject: Fry's expansion? was: RE: Radio Shack > > Marc Verdiell wrote: > > Here in the Valley, Fry's Electronics took over, and then made it so > > much better. Fry's is where you stop at lunch time, for amateur or > > professional stuff alike, and get an instant replacement for your > > fried LM7805. > > A few years ago, there was a rumor that Fry's was going to expand out of the > Valley. I wonder whether that might happen now that RS is on its way out. > > Bill S.

11 years, 4 months

2
1
0 0

It's time to restore the 11/45 - progress!

by jnc＠mercury.lcs.mit.edu

> From: Jacob Ritorto > I guess this crowbar thing tripping, is just its way of trying to > protect the rest of the system from overcurrent, right? Over-voltage. Voltage != current. :-) > And the dried up cap is one thing what could make it think there was an > overcurrent situation, correct? I think the concept is that the cap could have shorted out, thereby causing a too-high voltage to pass through it - or something like that! :-) In general, cause the circuit to mis-behave. > I don't know that I'm going to understand how to read the schematic. I struggle with the analog circuits too. Just keep plugging away at it, each will slowly start to make sense. (Not the most complicated/sophisticated aspects, but if you understand a lot of what's going on, I'm sure someone here can help on the tricky bits.) > Also going to try to find a manual that describes the power supply. DEC's maintainence/technical manuals are very good indeed for explaining how the analog circuits work - especially for those of us who can't just glance at a schematic and instantly, intuitively understand how the whole thing works. For me, reading them is really pretty much a must before trying to debug/repair analog stuff. > But what is a valid test once I find it? This is where you need test instruments; an ESR meter (although that's not a universal solvent), a capacitance meter, etc, etc. (Also an ohmmeter, to check for shorted caps.) > I don't have much electronics gear here. If you seriously expect to repair something like an 11/45, at a _minimum_ you need a decent 'scope. Don't even _try_ thinking you can do it without one. Fuhgeddaboutit. I like Tektronix 465's - they are common on eBay, and if you're patient, you can get one for $60-70. They are also a 'scope much used on these machines BITD. (We did.) Past that? Well, there are things that are nice to have (e.g. a de-soldering station), but you can often work around them (e.g. a pair of dikes and a solder sucker). A logic analyser would be nice, and I keep meaning to get one, but I haven't, yet, so they aren't essential. (Although for _some_ faults, a 'scope just doesn't cut it. If you can write a loop, fine. If not... time for a logic analyzer.) I'm trying to think what else is absolutely essential, past the 'scope (and the meter - you ought to buy your own, they aren't that much). Nothing comes to mind immediately - perhaps someone else here can add to the list. Noel

11 years, 4 months

2
1
0 0

Remember Coherent?

by lproven＠gmail.com

I could never afford it & figured I wouldn't understand it if I did. But it sounded really cool. Well, as of last month, it's now FOSS. http://www.nesssoftware.com/home/mwc/source.php -- Liam Proven ? Profile: http://lproven.livejournal.com/profile Email: lproven at cix.co.uk ? GMail/G+/Twitter/Flickr/Facebook: lproven MSN: lproven at hotmail.com ? Skype/AIM/Yahoo/LinkedIn: liamproven Cell/Mobiles: +44 7939-087884 (UK) ? +420 702 829 053 (?R)

11 years, 4 months

11
12
0 0

DEC MKA11 and/or M8261/M8163

by pbirkel＠gmail.com

I don't understand the role of the M8162 "Port MUX A module" and M8163 "Port MUX B module" that the field-guide claims to be part of the MK11. They aren't part of the MK11 as far as any documentation that I've read regarding it. At least the M8162 has a pair of 20ma-style SLU connectors on it, but no UARTs that I can see. Do these modules really belong to the MKA11, rather than the MK11? Or to something else entirely? Is the MKA11 (which I can't find documented online) a revised MK11? The field-guide seems to imply this given its entry for the M8164 which basically reads like this: M8158 MK11 U Address buffer module M8159 MK11 U Data buffer module M8160 MK11 U Control A module M8161 MK11 U Control B module M8162 MK11 U Port MUX A module M8163 MK11 U Port MUX B module M8164 MK11/MKA11 U Data buffer module (Replaces M8159) It seems to me that something is incorrect in the field-guide, but none of my researches have identified where the error is and what the right answer(s) might be. Anyone here have any experience/knowledge with/of the MKA11 and/or the M8261/M8163? Thank you, paul

11 years, 4 months

1
0
0 0

ISA ( PC ) 8" floppy disk CONTROLLER ???

by gerardcjat＠free.fr

Thanks Shaun !! If you find the interface card and associated documentation, I would be interested. Please, let me know My philosophy : DBIT adapter is probably a very good product ..... but If I can stand with ** genuine ** "old stuff", I would love it . --- L'absence de virus dans ce courrier ?lectronique a ?t? v?rifi?e par le logiciel antivirus Avast. http://www.avast.com

11 years, 4 months

1
0
0 0

It's time to restore the 11/45.

by jnc＠mercury.lcs.mit.edu

> From: Jacob Ritorto > Can anyone understand and explain the unibus a / unibus b concept? I've never personally worked on a machine with them separate, but the picture on pg. 15 of the 11/45 Processor Handbook (1971 edition), and accompanying text, should make what's going on pretty clear. You have the 'normal' UNIBUS ("UNIBUS 1" they call it), controlled by the 11/45 CPU, on which regular memory, devices, etc live. The CPU also has access, via a special path (I guess this was later named "FASTBUS"?), to two _separate_ banks of high-speed memory. Those memories are _each_ dual ported; one port to the CPU's direct path, the other to a second UNIBUS, ("UNIBUS 2"). So something on UNIBUS 2 could be talking to one bank of high-speed memory while the 11/45 CPU talks to the other bank - while at the same time, a DMA device on UNIBUS 1 could be talking to memory on UNIBUS 1. I.e. three separate memory transfers all going on _completely_ simultaneously. UNIBUS 2 does not have a 'bus master' - one has to be provided by plugging some PDP-11 into it. One can either plug another PDP-11 into UNIBUS 2 (forming a primitive multi-processor, one in which the two machines share access to the high-speed memory on the 11/45); or one can 'jumper' the two UNIBI (is that the plural?) in the 11/45 together, at which point DMA devices on UNIBUS 1 can do DMA into the high-speed memories (which they do not have access to, if the two are separate). The way grants, etc, work is pretty simple. (You can skip this part if you don't care about the really gory details. :-) UNIBUS connectors include BGn and NPG - in at one end of the cable/jumper, out at the other. So that short section of UNIBUS 2 (it's actually just a chunk of the 11/45's main backplane) can either have: - a pair of UNIBUS cables (one in, one out) to make it part of some other machine's UNIBUS; - one UNIBUS cables (in), and a terminator at the other end, to make it the last thing on that machine's UNIBUS; - a UNIBUS jumpers (in) to make it part of the 11/45's UNIBUS, with the 'out' UNIBUS connector on UNIBUS 2 leading to the rest of the 11/45's UNIBUS If you don't jumper UNIBI 1 and 2 together, the 'UNIBUS out' cable to the rest of the 11/45's UNIBUS is plugged straight into the CPU's 'UNIBUS out' slot (i.e. where the jumper would have plugged in if the two UNIBI were united). > Should I eliminate all this fancy bipolar and core memory and just use > an m7891? For debugging, yes; simplest is always best. But if you have the fancy bipolar or MOS (not core; the fast memory path only supports the first two), don't pitch it, it's probably rare and unusual; and once you have the machine running, you may want to play with getting it running. > If I did, would it be on the fastbus, unibus a or unibus b and would it > even matter? Has to be on UNIBUS 1. (UNIBUS 2 becomes part of UNIBUS 1 if the two segments are jumpered together.) Noel

11 years, 4 months

3
3
0 0

11/23 clock issue

by jnc＠mercury.lcs.mit.edu

> From: Holm Tiffe > Hmm.. it looks to me as if the Board is missing the jumper W1 Err..... no. :-) Noel

11 years, 4 months

2
1
0 0

Incandescent lights [Re: It's time to restore the 11/45.]

by jnc＠mercury.lcs.mit.edu

> From: John Kaur > If anyone has worked up a led replacement for the '45, would be of > interest. The original incandescents are not easy to find 'Back in the day', there were LED replacements available - I have no idea who from. They looked just like the bulbs, but had the red glass. (We replaced all the lights in our 11/45 with them.) Anyone know who/where/what they were? Or of a modern equivalent? Noel

11 years, 4 months

1
0
0 0

DEC fan silliness

by roeapeterson＠gmail.com

So I've got a BA11-N chassis (18-bit, 9xQ-cd slots) and the cardcage fan has failed. The damn thing is riveted in, I'm gonna have to drill. Strangely, the power supply fan has bolts/nuts. I've never seen DEC do something this silly before, but I'm sure there are stories out there...

11 years, 4 months

1
0
0 0

It's time to restore the 11/45.

by jacob.ritorto＠gmail.com

Hi, Having gotten the 11/34 rig up to a good spec, I'm sufficiently excited to tackle the 11/45. It's been powered off since 2004, when I briefly turned it on only to find a wild jumble of lights and that none of the front panel switches or knobs did anything to the lights. Couldn't get it to run or deposit values or *anything*. I therefore assumed it was badly broken and so left it until now. It has stayed perfectly high and dry but has gone to extremes in temperature as the storage isn't climate controlled (this is in western Pennsylvania). And there's a lot of dust. I'm not going for museum perfection, but want it to be very presentable (lobbying to keep it as my 'art' in the living room long term if it's presentable enough :) and functional. So I'm looking for tips on how to go about it? I was thinking: 1) Truck machine to living room, note positions of all wires / boards. Photograph, remove and clean dust from them. Place on antistatic bench. 2) Thoroughly blow out dust and debris, vacuum backplane and wipe down chassis and wires with damp cloth. 3) Map out desired hardware config: I have available two Fujitsu 160 disks, three Fujitsu M2333K disks and two Fujitsu M2372K disks. I need to decide how to rack and cable at least two, possibly up to four of them as the 8" ones have no mounting hardware. Operational status on all is "hopeful." I have two Emulex SC21s and an SC41 as well as an unmarked Xylogics Unibus SMD board. I'm also tempted to mount an RX02 drive as I have a controller and quite a mountain of floppies supposedly containing weird old stuff. I need to source an ethernet board and whatever cabling / bulkhead stuff follows. DZ11, its dist panel and a Diablo 630 printer would be nice, too. 4) This would also be a good time to broach the subject of whether or not the capacitors need special love, or if that just adds more risk of destroying something. Those familiar, please chime in as the archive is currently missing so I can't refer to the recent threads on this subject. Datapoint: I didn't mess at all with power supply / caps on my 11/34, which was stored right beside the '45 for the same timespan and it's running great now. Datapoint 2: with my amateur electronics skills / status, there's admittedly some risk just having me poking around in there, "learning" things :-\ Plus, I'm afraid of death from esoteric high voltages that I hear are present in these old power supplies. Is the 11/45 one of them? In a nutshell, this analog / power stuff is FAR FROM my forte; some hand-holding here would be most appreciated. 5) Insert an expendable Unibus module and power up; check & tune power. I need direction on how to go about this. Also, the bottom H742A power chassis isn't completely populated. Not sure if that's acceptable, on purpose or bad. 6) Reassemble, tidying up issues like missing / loose screws, rubbing cables, etc. along the way. 7) rt, 2.11BSD, rsx, rsts/e! (mostly via vtserver - I have a tu10 that I could get in on this deal, but its roller rubber has turned into goo and two cabinets in the living room is more than "pushing it." Later date on that puppy. ) Current module config starting from front of cabinet (yes, there are some gaps and M9200 jumpers I don't mention, too): M9301 + M787 M8114 M8115 M8112 M8113 M8100 M8101 M8102 M8103 M8104 M8105 M8106 M8108 M8107 M8109 M8110 g401 M7800 + M9200 jumper H214 G231 G110 H214 G231 G110 H214 G231 G110 Unibus cable runs out to third party external memory chassis, "Monolithic Systems Corp" Type MO v11/PDP11 P/N 300-0058-000, which is three quarters populated. If this memory is broken, I'm planning to use an M7891 instead (is that OK?). No Unibus termination after that. Is that weird / bad? Does this current config seem sound? Is there a problem obvious just from this description that would account for the unresponsive front panel? Here's the power supply situation: There are two H742A power chassis. Top contains h744, h744, h744, h744, h745. Bottom contains H745, H746, open, H744, open. big thx! jake

11 years, 4 months

7
14
0 0

It's time to restore the 11/45.

by jnc＠mercury.lcs.mit.edu

> From: Jacob Ritorto > Should I eliminate all this fancy bipolar and core memory and just use > an m7891? PS: I forgot to mention: that board, IIRC, _has_ to go into a Modified UNIBUS slot. Plugging it into something that's _not_ MUD will, I am pretty sure, fry something. Do you have a backplane with has MUD slots to plug it into? I _think_ DD11-C's and DD11-D's have them. > From: tony duell > A plain Variac does not provide isolation from the mains so you are > actually now working on mains-connected circuitry (read : dangerous and > you can't clip a 'scope on it). I'm clearly a little slow this morning: why can't you use a 'scope on it? > From: Mouse > Perhaps fortunately, it appears that here, at least, incandescents > aren't completely banned, just vanilla 100W ones. In the US, 'vanilla' 75W bulbs are now also banned (and I think 60W's are headed that way, too); 'specialty' bulbs (not sure of the exact definition - think coloured, etc) of 75W and 100W are still allowed. (As are, ironically, plain 150W and 200W!) Noel

11 years, 4 months

8
7
0 0

Prime?

by bbrown＠harpercollege.edu

I've heard something about a prime emulator (to run primos, premix etc).. does anyone know any info on where it is and how to get ahold of it? Anyone know of any actual prime hardware out there? Thank you! -Bob

11 years, 4 months

8
13
0 0

Heathkit H-8 Tape Sound Files?

by nf6x＠nf6x.net

Do any of y'all know of any archived tapes for the Heathkit H-8 computer that are online as audio files that I could record onto tapes, as opposed to image files containing the decoded data for use with emulators? So far, I've only found the latter, but would like to find the former for use with a real H-8. -- Mark J. Blair, NF6X <nf6x at nf6x.net> http://www.nf6x.net/

11 years, 4 months

1
0
0 0

Differences between PDP-11/83-84 M8190-AB/AC and AD/AE CPU cards

by jnc＠mercury.lcs.mit.edu

So I've seen some references which say that the M8190-AB and -AC (w-o/w FPJ11 FPP chip) are 15 MHz "11/73" CPUs for QBUS use, and the M8190-AD and -AE (w-o/w FPJ11) are 18 MHz "11/83-84" CPUs for UNIBUS use (via the KTJ11-B convertor, of course). (Of course, the /83 is nominally QBUS, but let's ignore that for the moment... :-) (And I'm not even going to try to give the KDJ11- suffixes that go with these... :-) However, I'm wondering if this is correct... I have a CPU board out of a 11/84 (one owned by DEC, no less!) which says M8190-AB on the handles, but the clock crystal says "18.432", and it has a 57-19400-09 J11 chip, which seems to be the 18MHz version (the 15Mhz seems to be -04). Comparing it to a 'stock' -AB, this one seems to have the same 74S472 PROMs (6 along the lower left-hand edge), PALs (top center and lower left), etc. But they also match the ones on a 'stock' -AE, too! So clearly an -AB/AC _can_ be _upgraded_ to an -AD/-AE... but are there actually any differences between an -AB/AC and an -AD/-AE, other than the speed? I don't have my /84 up yet, so I can't plug a stock -AB in and see if it works, but I'm starting to get the impression that except for the speed of the J11 (and the crystal), and whether or not it came with the FPJ11, all four of these boards are otherwise identical. Whether it's a 73, 83 or 84 depends entirely on whether it has PMI memory and the KTJ11-B UNIBUS converter (and the correct backplane, for the latter, of course). Anyone have an confirmation one way or the other? Thanks! Noel

11 years, 4 months

8
9
0 0

11/23 clock issue

by jnc＠mercury.lcs.mit.edu

So I'm debugging a dead PDP-11/23 board (M8186). The first thing I check is the clock; specifically the output of the first stage buffer-inverter (pin 16 of E4, a 74S240, upper right corner of page 2 of the prints), which is distributed to a number of places. Nada. Totally flat-lined. So I checked the input (pin 4), and it's sitting at about 2V. Also flat-lined. This does not seem good... :-) So here's my question: what's the likely fault here? The only thing upstream of that gate is the 13MHz crystal itself. So the fault has to be either the crystal or the S240 (which seems to be some sort of octal 3-state inverting buffer). Any guesses as to which? As usual, thanks in advance for any help! Noel

11 years, 4 months

2
1
0 0

It's time to restore the 11/45.

by jnc＠mercury.lcs.mit.edu

> From: Jon Elson > there is no part of the EUT that is at neutral potential > From: tony duell > With most 'scopes one side of the input is grounded -- you have a > coaxial cable with the shield connected to the 'scope case and true > ground. Ah. That's the part I was missing! I (naively :-) assumed that the 'scope's whole input amplifier would be 'floating', and the input signal would be taken as referenced to the 'ground' on the probe, which could itself be floating. Clearly not! (I'll have to look at the manuals/prints for my 'scopes - Tektronix 465's - to see if they are this way. Anyone happen to know, offhand?) Thanks! > In most, if not all, countries, one side of the mains is connected to > ground too. Yes, in the US that's code; neutral (aka 'return') is usually tied to ground at the main panel. (Well, at least in the state I live in - technically I suspect that it's under state law, not Federal, but I would assume the states are all the same, the way they are with commercial law.) Noel

11 years, 4 months

5
5
0 0

It's time to restore the 11/45.

by jnc＠mercury.lcs.mit.edu

> From: Jon Elson > Gee, our 11/45 (SN343) didn't have this, as far as I know. > This sounds more like an 11/70. Similar to the 11/70 in some ways, yes (a high-speed private memory bus), but very different in others (a second UNIBUS allowing another PDP-11 access to shared memory - nothing like that on the 11/70). Like I said, this is in the 1971 11/45 Processor Handbook (which I think is the first edition; I've never seen an earlier one), so I think it's original. I guess that manual's not online; if you'd like, I can scan that diagram and put it online. Noel

11 years, 4 months

1
0
0 0

MicroVAX 2000 with Network Interfaces problems.

by mattislind＠gmail.com

I have a MicroVAX 2000 that has suffered from a leaking battery. It has been cleaned and seems to be mostly working except for the network interface. The startup reports ?? NI 0011.700E V1.1 for the network interface. The switch is set for thin ethernet, and a 50 ohm T is in the connector with two terminators. What does the failure code mean? I cannot find any document identifying different failure codes. It seems that the software finds the version so at least something is working. Anyone that has an idea what is wrong? I will try to examine the content of registers at 200E0000 and 200E0004 and also if the ROM is accessible properly at 20100000 - 2011FFFF. But other than that, what can be done?

11 years, 4 months

2
1
0 0

It's time to restore the 11/45.

by jnc＠mercury.lcs.mit.edu

> From: Jacob Ritorto > Should I eliminate all this fancy bipolar and core memory and just use > an m7891? PPS: Why bother with memory at all, at least to get the CPU running at a basic level? Use the hack that someone here (I forget who, IIRC it was Johnny B.) reported, which is that you can store really small programs in the PARs - although in the 11/45, you're restricted to instructions of the form 00xxxx! Still, that's good enough for BR, CLR, INC, etc, etc. Noel

11 years, 4 months

1
0
0 0

Weekly Classic Computer Trivia Question (20150204)

by dpi＠dustyoldcomputers.com

This time lets refer to some classic fictional computers used in movies. Everyone probably knows about the HAL 9000 used in the movie 2001 a Space Odyssey. What was the name of HAL's sister computer in the movie 2010 Odyssey two? That was a warm up question. This one should be more difficult. What was the designation of the computer in the movie WarGames and what does it mean? And finally, As silly as it was the movie Hackers referred to the mainframe computer in the movie as a Gibson. Where did the term Gibson come from? -- Doug Ingraham PDP-8 SN 1175

11 years, 4 months

7
8
0 0

Terak 8510 keyboard

by simski＠dds.nl

hey, that is good news! seems it is quite easy to emulate with this info. maybe even to adapt in software from another keyboard from the same timeframe. thanks On 04-02-15 19:10, John Foust wrote: > At 04:05 AM 2/4/2015, Simon Claessen wrote: >> we have a fine specimen with extra floppy drive in our collection, but we lack a keyboard and cables. what type of keyboard was used? I can imagine that a standard keyboard controller chip was used so maybe a hacked together setup can be produced to boot the thing (we have media) > > Google "terak.8532-2.keyboard.specs.pdf" and you'll find the specs > in the Bitsavers archive. Eight bits parallel with strobe, in short. > > - John > > -- Met vriendelijke Groet, Simon Claessen drukknop.nl

11 years, 4 months

1
0
0 0

Weekly Classic Computer Trivia Question (20150204)

by tiggerlasv＠aim.com

>> Where did the term Gibson come from? > William Gibson, who coined the term ?Cyberspace? in his story ?Burning Chrome?. World-of-Warcraft players might recognize a certain quest, called "Hacking the Wibson". No doubt a play on the above. ;-) T

11 years, 4 months

1
0
0 0

VCF East online ticketing

by evan＠snarc.net

VCF East online ticketing is up and running: http://www.vintage.org/2015/east/

11 years, 4 months

1
0
0 0

MSV11-D debugging question

by jnc＠mercury.lcs.mit.edu

Finally getting back to this: > From: Brent Hilpert >> Again, I have a sitation where a bit is stuck on, and I'm curious to >> see if anyone has any insight into which chip (of 3) might be causing >> it (in an attempt to not have to try replacing them at random :-). > (Are they 4116 memory chips in use?) Yes. > a means to isolate which of the 3 points (ICs/pins) is the problem > might (not guaranteed) be: > ... > If the state is only faulty after one of the accesses it suggests the > according mem chip is the failure point. ... distinguish the accesses > to the upper and lower bank to try to isolate when the circuit enters > the faulty state, and see whether it's common to both banks or only one. Thank you! Thank you!! Thank You!!! That worked a treat; found the bad chip first time! Thanks again! Noel

11 years, 4 months

2
1
0 0

ISA ( PC ) 8" floppy disk CONTROLLER ???

by gerardcjat＠free.fr

For an OLD PC ( ISA slot ) obviously .... Does this "beast" ever existed ?? Does anyone recall some manufacturer's name ?? Have I any chance to find one on Ebay or other at this time ?? Or is "DBIT" adapter the only way to go ? --- L'absence de virus dans ce courrier ?lectronique a ?t? v?rifi?e par le logiciel antivirus Avast. http://www.avast.com

11 years, 4 months

9
15
0 0

Terak 8510 keyboard

by simski＠dds.nl

Hello all we have a fine specimen with extra floppy drive in our collection, but we lack a keyboard and cables. what type of keyboard was used? I can imagine that a standard keyboard controller chip was used so maybe a hacked together setup can be produced to boot the thing (we have media) -- Met vriendelijke Groet, Simon Claessen hack42.nl computermuseum

11 years, 4 months

3
2
0 0

SGI server

by sales＠elecplus.com

Not mine, not affiliated, if interested, please contact him directly. SGI Origin 300 Server Cabinet Full Height $295 Robert at ptemail.biz

11 years, 4 months

1
0
0 0

Tape Drive Capstans

by cctalk＠fahimi.net

Does anyone know if at any time in the past thirty years if the material used to make capstans has changed? I.E. can one be more confident of tape drives manufactured after some era to have non-goo capstan or is it that all tape drives (including ones manufactured now are ticking time bombs? Also how do you guys check capstans? Just stick long Q-tip in there? Thanks. -Ali

11 years, 4 months

19
37
0 0

Remember Coherent?

by jnc＠mercury.lcs.mit.edu

> From: Liam Proven > Well, as of last month, it's now FOSS. Ah! If we hadn't lost him (sigh), DMR could now look at the code itself* to see if they ripped off Unix... :-) Love this line from the intro to the documentation: "COHERENT is what UNIX used to be." Ain't dat de troof. Noel * https://groups.google.com/d/msg/alt.folklore.computers/-/5B41Uym6d4QJ

11 years, 4 months

3
2
0 0

Friden EC-130 Help

by marc.verdiell＠gmail.com

Kyle, drlegendre and Jim, Please keep sharing what you find out! I Just bought one of these machines, to keep company to my two other mechanical Fridens. It hasn't arrived yet. It was described as non-functional. So it looks like I will be asking similar questions soon. Marc > drlegendre <drlegendre at gmail.com> wrote > Hi Kyle, > While I certainly cannot claim any level of expertise in the matter, I do > happen to have a functional EC-130 here [...]Likewise, I have no service documentation for it. But if I can be of any > assistance, so far as providing voltage / resistance / component readings, > I'll try to do my best as time allows. >> Kyle Owen < <mailto:kylevowen at gmail.com> kylevowen at gmail.com> wrote: >> A friend of mine gave me a Friden EC-130 >> Pictures here: <http://imgur.com/a/OjxCn> http://imgur.com/a/OjxCn >> My understanding is that schematics are not available for the unit. Is that >> still correct? It wouldn't be a hard unit to reverse engineer; it's just a >> whole lot of components. >> >> If anyone has any advice to offer, it would be much appreciated. >> >> Kyle

11 years, 4 months

1
0
0 0

Remember Coherent?

by shawn-gordon＠cox.net

I still have the install floppies and books for some reason. I liked them as a unix reference. On 2/2/2015 11:06 AM, Liam Proven wrote: > I could never afford it& figured I wouldn't understand it if I did. > But it sounded really cool. > > Well, as of last month, it's now FOSS. > > http://www.nesssoftware.com/home/mwc/source.php > >

11 years, 4 months

1
0
0 0

Are the old archives ever going to be available?

by dzubint＠vcn.bc.ca

I'm aware that "something" happened at the end of October 2014 and the cctalk archives (http://www.classiccmp.org/pipermail/cctalk/ ) aren't currently available before then. Is this a permanent situation? I used to occasionally search through old archive postings for various VAX information and found it very useful. Just asking...I'm not trying to be pushy.

11 years, 4 months

3
2
0 0

LA75 wiring?

by quapla＠xs4all.nl

Quick Question, does anybody know the MMJ serial port wiring? I have a MMJ cable with on one side a MMJ plug and want to put a DB9 connector on the other end, but I can't find which wires (of the 6) are used and which does what. Thanks, Ed -- Dit is een HTML vrije email / This is an HTML free email. Zeg NEE tegen de 'slimme' meter.

11 years, 4 months

2
3
0 0

DECpc 433 (PCW10) manual

by witchy＠binarydinosaurs.co.uk

Folks, I rescued one of these from work yesterday, it's the slim desktop model with external drive enclosure. Inside there's a daughterboard with 483-33 processor and co-pro socket. On this daughterboard is a VGA port and rotary selector which either makes the machine work or not. (CMOS error beep code) This is a very multi-position selector, anyone have a book of words that explains what they all mean? Google and MANX have come up blank. Cheers, -- Adrian/Witchy Binary Dinosaurs creator/curator Www.binarydinosaurs.co.uk - the UK's biggest private home computer collection?

11 years, 4 months

2
1
0 0

Friden EC-130 Help

by kylevowen＠gmail.com

A friend of mine gave me a Friden EC-130. It's in pretty good shape, though it's missing quite a number of screws, as well as the bottom plate. Pictures here: http://imgur.com/a/OjxCn As you can see from the pictures, I don't get any distinguishable digits on the CRT. Thankfully, most of the logic does seem to be working; entering too many digits before the decimal place as set by the rotary switch results in an overflow upon hitting enter. Entering thirteen 9s and dividing by 1 takes about 2 seconds (the button stays depressed; quite cool), whereas simple adding and subtracting returns the result right away. Keyboard feels good, and you can see the CRT modulate differently depending on what's to be displayed. I've tried the obvious thing of reseating boards and rotating the pots back and forth a bit, to no avail. My understanding is that schematics are not available for the unit. Is that still correct? It wouldn't be a hard unit to reverse engineer; it's just a whole lot of components. If anyone has any advice to offer, it would be much appreciated. Thanks, Kyle

11 years, 4 months

3
5
0 0

Pair of HP 1000 E-Series minicomputers on eBay

by gerardcjat＠free.fr

Hello Tony Beeing an HP lover too, I am just wondering ..... Are you able to "see" this kind of item, on ebay, from UK ?? For myself, beeing in Paris, ( France, not Texas ;-) ) .... I am denied acces to these kind of item on ebay !! Is there a "work around" trick ??? Regards --- L'absence de virus dans ce courrier ?lectronique a ?t? v?rifi?e par le logiciel antivirus Avast. http://www.avast.com

11 years, 4 months

2
1
0 0

2026

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

2000

1999

1998

1997

test-drb