May 2017 - vcf-midatlantic - lists.vcfed.org

Museum closed today
by Evan Koblentz 28 May '17

28 May '17

Our museum is closed today and will reopen next weekend.

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Animated graphic needed
by Jonathan Sturges 28 May '17

28 May '17

So my understanding was that real burn-in required a display technology dependent on phosphor, like CRTs or plasma, so I have long understood that LCD was immune to this. What would give some handheld LCDs persistence? And would a motion GIF be sufficient? I didn't bother to check but that HAS to be compatible with Android 4.4... -Jonathan Date: Sun, 28 May 2017 04:05:15 -0400 From: Evan Koblentz <evan(a)vcfed.org> To: Vcf <vcf-midatlantic(a)lists.vintagecomputerfederation.org> Subject: [vcf-midatlantic] Animated graphic needed Message-ID: <79e1380f-e3ca-4638-82b9-27bfd4ab66bd(a)vcfed.org> Content-Type: text/plain; charset=UTF-8 > Some of our museum info kiosks, aka the cheapest Android tablets available, are showing signs of > burn-in from the VCF logo screen saver. > I don't know if this is literally old-fashioned "burn it" or some other technical issue.

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Radio Shack archives aution
by Evan Koblentz 28 May '17

28 May '17

Fyi: http://www.electronicdesign.com/communications/radio-shack-close-most-retai… ------------------------- Evan Koblentz, director Vintage Computer Federation A 501(c)3 educational non-profit Evan(a)vcfed.org (646) 546-9999 www.vcfed.org facebook.com/vcfederation twitter.com/vcfederation

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ADM-3A display problem
by Garrett Nievin 26 May '17

26 May '17

I'm restoring a Lear Siegler ADM-3A, and I'm not the most CRT-savvy guy around (but I did really enjoy Ian's excellent class at the most recent VCF-E). Attached is a photo of the issue. If I crank the brightness to clearly see the raster, I can see that the text is actually displaying as dark instead of bright. Pointers? Cheers, Garrett

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sun SparcStation 2, video frequencies
by Herb Johnson 26 May '17

26 May '17

Someone asked me, about connecting modern monitors to a SparcStation 2 with a CG6 8-bit color framebuffer. If you acutally have a VGA-type or LCD type *modern* monitor hooked up and running, please send me details. Now - I know plenty about video and scan rates and fixed frequency monitors. I don't need lessons in wiring up 13W3 connectors, sync-on-green. I know about sense-pins or "ID pins" which tell these video cards, "I'm monitor X, change your video to Y". OK? I'm not asking to be "schooled" on the subject. What I'm asking is what an electrical engineer would ask (that's me). What are the damn actual, real, video signals this card puts out? As in mode X: (sense pins grounded) horizontal frequency ? vertical frequency ? frame rate ? if you want, "video frequency in Megahertz" which isn't useful And yes, I searched the Web, and it was uninformative on "cold" searching. Active users of Sun may know where to go. Lots of links are dead, or under-informative, or lessons in video. My site has such lessons already! What I did find, are references to Sony monitors sold by Sun for use, which are GDM-1662 and GDM-1962. I got what I *think* are Sony's fixed frequencies of use. I did not get the magic "sense pins grounded" on those monitors. I'll not quote here what I learned on those monitors, you can send that along if you wish, that will confirm what I found. Here's a more general question, related of course. Otherwise - people who ask me about monitors for old computers, ask for a magic box. It's variously called "a converter" or "frame buffer" or "adapter". they think it magically changes video frequencies, even stores a frame of video! But most don't; the simplest just rewire 13W3's to hook to HD-15 connectors, with some toggles for the sense pins. some may play with sync signals. But...this is the year 2017, not 1997 or even 2007. There may WELL be "magic boxes" now, that have whole computers in them, that DO capture a frame and resend it. If anyone knows of one of THESE, which costs less than $100 - and it *works*, that matters for some reason - I'd like to know. IF it costs $250, that doesn't help - these are hobbyists asking, not video engineers. Thanks. Sorry for the long post, but I'm not looking for history lessons or video-signal lessons. Herb Johnson -- Herbert R. Johnson, New Jersey in the USA http://www.retrotechnology.com OR .net

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Virginia guys...
by William Sudbrink 26 May '17

26 May '17

Did any of the Virginia crew see this: https://washingtondc.craigslist.org/nva/zip/6147194618.html There's a guy in Dale City emptying out a storage shed: I am a retired engineer and am in the process of moving back home (out of state) I am emptying a 12 X 22 garage storage shed of 50 years accumulation of hardware, tools, furniture, automotive parts-filters-accessories, electronic parts and accessories, Ham Radio parts and accessories and household items. All will be placed on the curb for free pick-up hour by hour until the shed is empty.( NO BROWSING IN SHED OR GARAGE) No saving or holding, first pick-up gets it some or all FODDER FOR FLEA MARKETS OR YARD SALES! --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

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Results of Jason Scott collection rescue
by Evan Koblentz 26 May '17

26 May '17

Anthony S. and I took a Uhaul to Jason's house today and rescued most of his vintage computing collection. I'll never remember everything -- we filled the 9-foot cargo van three layers tall! Following are the highlights: - Large amount of common 8-bitters in mediocre condition. Half a dozen Apple ][ plus/e/c/GS/Laser; a few Vic/64 systems; one or two TRS-80; one or two TI-99/4A; etc. .... also some Sun systems and a pair of DEC Rainbows - Several DEC terminals in mediocre condition - A bunch of small tape drives etc. - Miscellaneous peripherals - Xerox-branded terminal that appears to be an ADM or similar - Commodore PET case with some other computer inside it (we didn't have a chance to open it but someone wrote "MM-1" in market on the back) - An awesome homemade videogame controller unit for a PC, might have to be installed in our workshop :) - NeXTstation and monitor, just like the one we got running in the museum a few weeks ago. Nice to have a backup! Funny story: we went an hour out of way to visit Sridhar and pick up something. We ended up visiting his father and picking up nothing, due to a fairly hilarious misunderstanding. ________________________________ Evan Koblentz, director Vintage Computer Federation a 501(c)(3) educational non-profit evan(a)vcfed.org (646) 546-9999 www.vcfed.org facebook.com/vcfederation twitter.com/vcfederation instagram.com/vcfederation

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Re: [vcf-midatlantic] COBOL
by VAXman＠tmesis.org 26 May '17

26 May '17

Dave McGuire via vcf-midatlantic writes: >On 05/17/2017 07:33 PM, william degnan via vcf-midatlantic wrote: > ..I >used cobol when I worked at dupont tso/JCL (Damn autocorrect) > > Cobol >is obsolete though. My professional opinion > > Your bank statement would disagree with you. > > Cobol is *out of fashion*. Obsolete doesn't mean quite the same >thing. I still have customers actively developing their application with COBOL. With extensions in the compiler, they make extensive use of VMS RMS ISAM files. I stil can't make head-or-tails of those damn PIC statements.

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ADM-3A display problem
by Herb Johnson 25 May '17

25 May '17

I own and have repaired some ADM-3A terminals, and I have electronics experience from the era. I did not see the posted image, from the VCF Web archive of messages. I just walked through the ADM-3A Maintenance Manual, which is on Web online archives. I did not see any "invert video" DIP switch setting. I did not see any description about how to invert video. And - at a glance - I did not see anything on the schematic on the logic board, which suggested a simple means to invert video. Of course I may have missed something; or my manual may not match the actual terminal. But I'm confirming the owner's impression that there's not likely a "toggle switch" in play. I'm afraid, the apparent inverted video, may be a real issue and not just some inadvertent setting. So: it's either a deliberate "mod" for purpose, or some logic failure. I doubt it's a monitor failure - that can be diagnosed, by using an oscilloscope to look at the incoming CRT monitor signal, to see if it is standard NTSC type video. This calls for technical experience and use of an oscilloscope. An oscilloscope will show actual signals. If there is a mod, jumper or failure, "walking through" with schematic and oscilloscope will find it. The logic board should be inspected for any wiring modifications. The board can be removed and decabled for such inspections. Be VERY CAREFUL because 1) various pieces of insulating "cardboard" are EXTREMELY fragile, 2) there's risk of shock from the 15,000 volts on the CRT - a charge that the "tube" retains after power-off, and 3) of course any physical issues from handing old electronics, boards, cabinets. Standard disclaimer: I'm not responsible for loss, injury or damage. Use any information I provide at your own risk. I may be wrong, confirm anything I've suggested. Herb Johnson -- Herbert R. Johnson, New Jersey in the USA http://www.retrotechnology.com OR .net preserve, recover, restore 1970's computing email: hjohnson AT retrotechnology DOT com or try later herbjohnson AT retrotechnology DOT info

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Computing time in BASIC
by Evan Koblentz 25 May '17

25 May '17

Suppose I want an Applesoft (Microsoft) BASIC program to do something for a certain amount of time as measured in seconds or minutes. FOR-NEXT loops don't align to any real increment -- they just count based on how fast the processor can go, right? If so, then how do you make something happen for a time amount? ------------------------- Evan Koblentz, director Vintage Computer Federation A 501(c)3 educational non-profit Evan(a)vcfed.org (646) 546-9999 www.vcfed.org facebook.com/vcfederation twitter.com/vcfederation

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