September 2018 - vcf-midatlantic

Re: [vcf-midatlantic] Anyone have a spare PCjr TV adapter?
by corey cohen 25 Sep '18

25 Sep '18

> On Sep 25, 2018, at 12:38 PM, Jeffrey Golas <jeffg(a)junknet.net> wrote: > > I had a new in box one somewhere. > > Jeff Awesome if you can find it. corey cohen uǝɥoɔ ʎǝɹoɔ Mobile: +1 917 747 1408 Sent from my iPhone

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Anyone have a spare PCjr TV adapter?
by corey cohen 25 Sep '18

25 Sep '18

And no chuckles keyboard jokes please.... Thanks, Corey corey cohen uǝɥoɔ ʎǝɹoɔ Mobile: +1 917 747 1408 Sent from my iPhone

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Anyone have a spare PCjr TV adapter?
by Jeffrey Golas 25 Sep '18

25 Sep '18

I had a new in box one somewhere. Jeff

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Re: [vcf-midatlantic] Maker Faire
by VAXman＠tmesis.org 25 Sep '18

25 Sep '18

Evan Koblentz via vcf-midatlantic <vcf-midatlantic(a)lists.vcfed.org> writes: > >>> What was the dry ice for? > >It goes in the cooler under regular ice. We brought a case of water and >some soda. OK. I usually get dry ice when I transport homemade ice cream to events. I can uaually get away with simple ice for keeping drinks cold.

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Re: [vcf-midatlantic] Maker Faire
by VAXman＠tmesis.org 25 Sep '18

25 Sep '18

Evan Koblentz via vcf-midatlantic <vcf-midatlantic(a)lists.vcfed.org> writes: > >World Maker Faire was as awesome as it is every year. > >Corey, Jeff B., me, and Corey's son/sister all helped at the VCF booth. > >Here's a video and some pictures taken by Jeff: > >https://drive.google.com/file/d/1K6YqRYdXWyYUCetOZNhtzAJwoy0BtLmv/view?usp=… > >As always, we saw other members of this group; many friends-of-VCF; >Brian from Hackaday; people who remembered us from other events; tons of >people who were astonished to see the machines of their childhood >up-and-running; and a few offers of potentially interesting donations. > >Our booth was filled with visitors almost the entire time. I really wanted to get there again this year. I wanted to see the VCF display and to speak with the guys at Magnitude.IO too, but I couldn't due to a family gathering. >Everything was great until 10 minutes before closing time Sunday night, >when I DROPPED MY LEGO ROBOT ON THE PAVEMENT .... "disassemble". Good >thing it happened at the end of day two, not the start of day one! Now I >get to make a new one. > >Special thanks to Jeff for driving and Dean for providing a cooler + dry >ice. What was the dry ice for?

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Maker Faire
by Evan Koblentz 24 Sep '18

24 Sep '18

World Maker Faire was as awesome as it is every year. Corey, Jeff B., me, and Corey's son/sister all helped at the VCF booth. Here's a video and some pictures taken by Jeff: https://drive.google.com/file/d/1K6YqRYdXWyYUCetOZNhtzAJwoy0BtLmv/view?usp=… As always, we saw other members of this group; many friends-of-VCF; Brian from Hackaday; people who remembered us from other events; tons of people who were astonished to see the machines of their childhood up-and-running; and a few offers of potentially interesting donations. Our booth was filled with visitors almost the entire time. Everything was great until 10 minutes before closing time Sunday night, when I DROPPED MY LEGO ROBOT ON THE PAVEMENT .... "disassemble". Good thing it happened at the end of day two, not the start of day one! Now I get to make a new one. Special thanks to Jeff for driving and Dean for providing a cooler + dry ice. ________________________________ Evan Koblentz, executive 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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VCF Repair Workshops 2019
by Jeffrey Brace 24 Sep '18

24 Sep '18

Going to start reserving dates for the repair workshops. Anyonw know od any conflicts with these dates? January 5 February 2 March 2 April 6 -- ========================================= Jeff Brace Vice President Vintage Computer Federation

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Hello! and a Commodore 64 Question
by Michael Pohl 24 Sep '18

24 Sep '18

Hi- I'm new to the group after meeting Evan at Infoage recently. My 12 year old son is a vintage computer/vintage video game fan. We picked up a non-working Commodore 64 as our first project. We watched a few YouTube videos and ran the suggested basic diagnostics and found that the power supply produces the correct voltages, the fuse is good, and there is the correct voltage at several key locations on the board. Connecting the RF modulator to a TV doesn't change the picture (still only snow) and connecting via the 8 pin jack to a Commodore monitor produces nothing. The computer is an cosmetically good shape and does not appear to have ever been opened up as the RF shield was intact. I note that only three of the large chips are on sockets. Any suggestions for next steps? Thx, Mike

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Oh boy (Maker Faire)
by Evan Koblentz 22 Sep '18

22 Sep '18

3:15am: Finished robot, finished code, finished packing for Maker Faire. 4:15am: Wake up to go to Queens. Yay, I get to sleep for a whole hour! Looking forward to seeing many of you this weekend.

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Fwd: Floating point math in FORTRAN IV on PDP-8
by Kyle Owen 22 Sep '18

22 Sep '18

I sent this over to cctalk and haven't found a taker to try out my FORTRAN code on another PDP-8 yet. Might any of you be able to try this out? At VCF MW this past weekend, I was playing around with an FPP8/A stuffed into a PDP-8/M with a fan removed. This hex-wide two-board set will happily work in a quad-wide backplane, as it needs no signals that an 8/A would otherwise provide. I wanted to benchmark the FPP8/A with the software emulation that FORTRAN IV supposedly does. Mind you, I also don't have an EAE in mine, so software emulation for integer multiplication/division would also be used. I tried running a simple program to print some natural logs and square roots, which ran quite well with the FPP8/A in place. Without the FPP8/A...all of the results were wrong. Significantly. Negative numbers in many cases. No clear pattern as to what it's doing. Would anyone be able to try my program on some other real hardware (or another emulator) to verify? With and without EAE would also be desirable. I'm not sure how to disable the EAE in SIMH, else I'd try that too. Here's what SIMH looks like with my program: PDP-8 simulator V4.0-0 Current git commit id: d35b8725 sim> at rk0 disk2.fortran.rk05 sim> b rk .TYPE FLOAT.FT DO 50 I=1,100 F = FLOAT(I) G = SQRT(F) H = ALOG(F) WRITE(4,100) F,G,H 50 CONTINUE 100 FORMAT(' ',F12.6,F12.6,F12.6) END .R F4 *FLOAT/G$ 1.000002 1.000002 0.000000 2.000002 1.414215 0.693147 3.000002 1.732053 1.098614 4.000002 2.000002 1.386296 5.000002 2.236070 1.609439 [snip] 98.000001 9.899495 4.584968 99.000000 9.949874 4.595121 100.000023 10.000008 4.605171 . Much appreciated, Kyle

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