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One more try - Can you ID this S-100 Serial board?

by drlegendre＠gmail.com

"My guess would be cost. Those headers back then were somewhat expensive due to the heavy (30) gold plating." Wow. I never even considered that a header could be more costly than a 74LSXXX chip - doesn't make sense. But then again, I wasn't in the field back in that day. On Thu, Oct 1, 2015 at 10:48 PM, Tothwolf <tothwolf at concentric.net> wrote: > On Thu, 1 Oct 2015, drlegendre . wrote: > > Also, I'm curious about the 50-pin headers.. why were they never >> installed? All of the other work was done, all the expensive parts (chips) >> are in-place - so why not a couple of cheap headers? Yes, a few resistor >> SIPs are gone, as is one chip missing, but still, you get the point. >> > > My guess would be cost. Those headers back then were somewhat expensive > due to the heavy (30) gold plating. > > I found out today that as of August 3M has discontinued their 3000 series > gray box headers and the last time buy on them was October 1st. They are > replacing them with the D3000 series made with black fiberglass reinforced > nylon instead of the gray nylon they've always used. (3000 series datasheet > attached) > > The part numbers for the 50-pin headers without eject levers for 1/16" > thick pc board would be 3433-5002. Mouser shows some stock, however their > system may or may not be correct and they might try to substitute the newer > D3000 series. > http://www.mouser.com/ProductDetail/3M/3433-5002/?qs=%2fha2pyFadugF4%2fyP%2… > > I also spotted some 3433-5402 on eBay at a reasonable price that might > work, however those use a roll pin to attach the eject levers, so they are > much harder to remove than the ones that used snap-in eject levers. > http://www.ebay.com/itm/3M-3433-Locking-Ejector-Header-50-pin-right-angle-g… > > Also, don't forget about C2. It and C1 were probably a matched set for the > crystal.

10 years, 7 months

DEC handles

by jnc＠mercury.lcs.mit.edu

> From: Stephen Lafferty > When I bought the Omnibus prototyping board from Douglas Electronics by > phone a few years ago, the lady I spoke to offered to include handles > ... > I have not found the handles mentioned on their website but I might > have missed it. They do still have a few (~100) left, but you have to contact them, they are indeed not on the Web-site; $.55 each. Grab them while they're there! :-) Noel

10 years, 7 months

Aresco Newsletters

by mikolaym＠yahoo.com

Hi all, Out of curiosity, did anybody on here subscribe to any of the newsletters published by a company called Aresco back in the late 70s and early 80s? These newsletters were VIPER (Cosmac VIP), Paper (Commodore PET), Source (Exidy Sorcerer), and Rainbow (Apple II). Aresco also published a series of books by Tom Swan titled PIPs for VIPs. I own several issues of VIPER, but I'm still looking for copies of the others. Does anybody have these newsletters in their collection? Matt

10 years, 7 months

Robotron K1840 .. (11/780 alike..)

by holm＠freibergnet.de

Hi, some people from the "Rechenwerk Halle" (http://9hal.ath.cx/usr/digital-ag/projekte/andere/museum/) ..a bunch of people that is interested in historical computing got an Robotron K1840 DEC 11/780 clone lately and they try to get it running again. (freinds of mine). Unfortunately a thing called SKR Busadapter (Massbuss adapter) and the entire console computer are missing. So far as I know is the main CPU 100% compatible to the DEC original using an UNIBUS System, PCBs are exchangeable, but the Console Computer is not. In The K1840 this is a K1620 Computer, the CPU is build from 8 Bit NMOS slices (U830) and ordinary EPROMs (https://de.wikipedia.org/wiki/U830C) using a mechanical different PCB System. The same system was used in the K1630 PDP11-alike (see below) which had an MMU (K1620 has none). The Main difference that's preventing unpatched OSes are the U834 Bus interface ICs, that must be software configured before the devices can be accessed from the QBUS-like System Bus. The U834 are containing the Bus drivers and all needed registers for interrupt and DMA and the entire address decoder logic needed for QBUS Systems which simplified the interfaces somewhat. Nevertheless of that progressive design, it was the worlds slowest PDP11.. In the K1840 ordinary TEAC FD55FV Floppies (2x) where used for the console System to boot up the system. So far so good (or bad). There are a few things that I want to know now.. I know that in the original 11/780 the Console CPU was an 11/03 with some interface to load the VAX Microcode in to the main CPU. Do you think it is possible to use an ordinary 11/23 instead? What Floppy Controller was used in the original, I know that there was a single 8" floppy drive in the 11/780 and don't think that the controller was the usual RX01 or RX02 System...? That's an article from the german magazine C't about the people which got the K1840: http://www.heise.de/newsticker/meldung/Rechnende-Schrankwand-Computermuseum… That's the K1840 on the left: http://9hal.ath.cx/usr/digital-ag/log/K1840_im_Rechenwerk.jpg and The K1630 .. PDP11 not so "clone" on the right. I don't think that the Tape drive was shipped with that machine, the bulgarian original looked different so far as I remember.. Is there someone that would help out them with missing hardware/software? Regards, Holm -- Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583 www.tsht.de, info at tsht.de, Fax +49 3731 74200, Mobil: 0172 8790 741

10 years, 7 months

IBM 026 - Decision Data 8010 card punch on Ebay in Germany

by mattislind＠gmail.com

Not really a 026 but maybe contemporary with the 029: http://www.ebay.de/itm/Historische-EDV-Lochkartenstanzer-Card-Punch-von-197… Not mine.

10 years, 7 months

DEC handles

by jnc＠mercury.lcs.mit.edu

> They still have them. They pulled the bin and put your name on it. Great, thanks very much! Just called them up and ordered the whole shebang. > It's about 100 (my guess) pieces Your guess was very accurate - actually, 105! > I already did a lifetime buy myself. If anyone needs a _few_ (between boards I already have that need them, and future needs, for some boards I am building, most of these are spoken for), let me know. Noel

10 years, 7 months

DEC handles

by jnc＠mercury.lcs.mit.edu

> From: Joseph Lang > How many do you want? How many do I need, or how many do I want? :-) I'm tempted to buy the whole bin (unless it's like a 55 gallon barrel :-), and hold onto them for other CCTalk people who need them. Maybe this will work: if you find them, point them out to the store people, and tell them I'll call? Would that be the easiest thing for you? Thanks! Noel

10 years, 7 months

ESR Meter Recommendations

by seefriek＠gmail.com

I'm going to be working on my 11/730s power supply, so I'm in the market for an ESR meter. I've seen some (older) recommendations for the AnaTek 'Blue' and various 'Dick Smith' derivatives. However, eBay is flooded with knockoff Mega328 based ESR/Transistor/SCR/etc. testers all looking like: http://www.amazon.com/DROK-Multifunction-Mega328-Transistor-Capacitor/dp/B0… Anyone had any experience with one of these devices? KJ

10 years, 7 months

ESR Meter Recommendations

by marc.verdiell＠gmail.com

I have been using the BK Precision 879B: http://www.testequipmentdepot.com/bk-precision/lcr/879b.htm?ref=gbase&gclid= CKj82-uIoMgCFRNrfgodYOYOvA It's at a completely different price point ($250-ish), and much more than an ESR meter - but it's a bargain for a full R,C,L,Z meter. Very useful to know not only the ESR, but the actual value of the capacitance (which for big power supply caps could have diminished significantly over the years). It can measure components at 100Hz, 1000Hz and 10Khz. You could not justify it for a single power supply repair, but if you do a lot of old electronics restoration projects, it is a precious tool to have. I couldn't live without it now. You can see it in action in the middle of this video here, in this case exonerating a capacitor that I sure thought was the cause of my power problem, but turned out to be perfectly good: https://www.youtube.com/watch?v=lqD6xVI6qNs Marc ====================== From: Ken Seefried <seefriek at gmail.com> Subject: ESR Meter Recommendations I'm going to be working on my 11/730s power supply, so I'm in the market for an ESR meter. I've seen some (older) recommendations for the AnaTek 'Blue' and various 'Dick Smith' derivatives. However, eBay is flooded with knockoff Mega328 based ESR/Transistor/SCR/etc. testers all looking like: http://www.amazon.com/DROK-Multifunction-Mega328-Transistor-Capacitor/dp/B00 NKY3M1W/ref=sr_1_16?ie=UTF8&qid=1443561246&sr=8-16&keywords=esr+meter Anyone had any experience with one of these devices? KJ =====================

10 years, 7 months

Ping to Tim Shoppa

by jhfinedp3k＠compsys.to

This post is for Tim Shoppa. This have seen your replies every so often on classiccmp, so you don't seem to be totally out of touch. If you are reading this, Alan Frisbie and I would appreciate some help. Allan can be reached at the address to which I sent a copy. Jerome Fine

10 years, 7 months

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