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Re: Friden (was Silly question about S-100 and video monitors)

by Rick Bensene

Just to add, interestingly, Singer also purchased General Precision from Librascope. Librascope/General Precision were the folks that had earlier acquired Royal-McBee. Royal-McBee developed the wonderful (some consider the first "personal" computer) LGP-30 vacuum-tube, magnetic drum computer that was designed by Manhattan Project theoretical physicist Stanley Frankel. Frankel had quite a legacy in the world of computing, having contributed to the design of the delay-line-based Packard Bell PB-250(with Max Palevsky), and development of a custom high-speed computer for Continental Oil Company called CONAC (used for data reduction of sounding operations search for oil deposits). Frankel also developed an early electronic calculator design that was purchased by Smith Corona/Marchant (SCM) and produced as the CRT-display SCM Cogito 240 calculator, augmented with Square Root as to Cogito 240SR. Frankel also collaborated with SCM on the development of the logic for the first set of LSI integrated circuits that were used in the later Nixie-tube display Cogito calculators. He also developed a very interesting calculator, based somewhat on the principles of the LGP-30 computer for Diehl in West Germany. The machine was fully transistorized and used only 142 transistors in its logic. It was based on magnetostrictive delay lines (two of them), and was a fully microcoded architecture, I believe the first electronic calculator to be completely microcoded. Since read-only memory (for the microcode) was either physically very large, or complex and expensive to build at the time (diode ROM, wire rope ROM), the microcode was loaded into the calculator at power-up time from a two channel punched metal tape. One channel provided the clocking, and the other channel provided the bits. It took just under a minute from when the calculator was powered on until the microcode was loaded into a delay line, and from there, all operations of the machine were controlled by the microcode in the delay line. The machine was able to be implemented with so few transistors because the microcode word was quite wide, and was designed so that it was sequentially interpreted as the bits streamed out of the delay line, so not all that many flip flops were needed. Working registers were stored in the other delay line, along with program steps (yes, the machine was programmable). The design was very elegant. The machine debuted as the Diehl Combitron, and the cool thing about its design was that it was really easy to augment by just changing the microcode tape (which was quite easily done...bugfixes could be easly installed even by end-users, though such was discouraged). Soon after the Combitron was introduced, an augmented version was introduced called the Combitron-S that added a small amount of I/O circuitry and additional microcode to implement operations to allow the addition of an external punched paper tape reader/punch. An interesting aspect of electronic calculator history is that there are a number of people whose names pop up at various points in time during the evolution of the technology. Frankel was one of those, along with a cast of a few others, all of whom had major impacts in the realm of electronic calculator (and the eventual evolution of the electronic calculator into what became the microcontroller/microprocessor that spurred the development of the personal computer).

2 years, 8 months

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Re: VCFMW Anybody got an Emulex QD21?

by Mark Matlock

Jon, I have an Emulex QD21 that I could part with. I was hoping to attend VCF MW but it looks very doubtful at this point. I also have a spare DEQNA or DELQA. I have not tested these boards to verify that they work although I could test the ethernet boards on a PDP-11. Hans-Ulrich Hölscher mentioned work he did testing MicroVAX II transfers with Lee Gleason’s MicroVAX I project to transfer disk images on bare metal (no-OS) MicroVAX systems. I think that would be your best bet to recover your ESDI disk. If you don’t have any luck at the VCCF MW getting what you need, send me an email and we can work something out. Best, Mark

2 years, 8 months

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SDF Interim Computer Festival

by Tarek Hoteit

FYI, SDF retro computing and home brew exhibition is scheduled for September 30 to October 1 in Seattle WA . Link to the exhibit is at https://sdf.org/icf/ and https://icm.museum/ - - - - Tarek Hoteit tarek(a)infocom.ai +1 360-838-3675 https://infocom.ai

2 years, 8 months

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Little Databases

by Adam Thornton

Have you considered sqlite3? It's a SQL engine, but the backend is just a file. So it doesn't support concurrent access by multiple users, but if that's not a concern, it gives you the ability to do real SQL queries without the bother of setting up an RDBMS. Adam

2 years, 8 months

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Plotter or Chart Recorder pens - in UK

by dave.g4ugm＠gmail.com

I have found some plotter pens. Ons pack says Calcomp 104x, 1023. The other I can't trace. They look like they clip into ring. Pics here. https://1drv.ms/f/s!Ag4BJfE5B3onnqhG_uReQsCndYafvg?e=WpT5nw I have a few more of the Calcomp, packets of the un-branded sort. Free for the cost of postage Dave

2 years, 8 months

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IBM 1620 Model 2 software wanted

by Dave Babcock

To all, Some 20 years ago, I led the Computer History Museum's restoration of an IBM 1620 Model 1 computer. Our team was successful in both bringing the machine back to life and collecting a massive amount of manuals, books, and software for the machine. Most notable the John Maniotes collection. I can safely say that CHM has the largest collection of IBM 1620 material in the world. We are still looking for IBM 1620 Model 1 manuals to add to collection. Please let me know if you have anything that we might be missing. In the past 2 years, several people have been writing simulators for the IBM 1620 Model 2 that go well beyond SIMH's instruction-level simulator. These simulators are based on the logic diagrams of the machine and implement unusual corner cases as well as documented functionality. One of the simulators has a text-based front panel while another one has a full true-to-life graphical front panel. It's not my place to formally announce either program, that's for the creators to do once they complete their implementations. I've been consulting with the engineers and am reaching out to the broader community for help. What they need, and CHM would be very interested in adding to its IBM 1620 collection, is original software specifically for the IBM 1620 Model 2. Of particular interest are the IBM 1620 Monitor II and IBM 1620-2 diagnostics, but any Model 2 software would be helpful to their efforts. Please let me know if you have and IBM 1620 Model 2 software or manuals. Thanks, Dave Babcock

2 years, 8 months

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Signetics N8220B ??

by Holm Tiffe

Hi guys, I have 8 "new" Chips from Signetics, they are labeled: S7536 N8220B and on the backside between the pins "8220". Does anyone know what they do? My search with google and in the 1976 Signetics Date Manual (from Bitsavers) wasn't helpful... Thanx in advance, Holm -- Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, Goethestrasse 15, 09569 Oederan, USt-Id: DE253710583 info(a)tsht.de Tel +49 37292 709778 Mobil: 0172 8790 741

2 years, 8 months

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vcfmw

by Paul Anderson

If anyone wants any DEC gear brought up to wcfmw, please contact me off list. If anyone is driving out from the NJ area, I have a few pieces of audio equipment I need to get transported to IL. I also collect US and foreign coins and currency, and am interested in buying or trading for DEC items. Thanks, Paul

2 years, 8 months

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Gould Systems 32/77 Acquired (superminicomputer)

by Eric Moore

https://youtu.be/utAd_uZryDE

2 years, 8 months

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Apple 1

by Murray McCullough

Classic computers have a value in our capitalist society. Take the Apple-1: Its value can be in the $100,000s. One is for sale now: ~ $200,000. Next seems to be the Kenbak-1 valued somewhere around $50,000. Now, I’m not suggesting money is the epitome for evaluating our hobby but it goes a long way to explaining its longevity. Happy computing. Murray 🙂 Add. I'm unable to get the output from your site but hope to contribute in some small way.

2 years, 8 months

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