- vcf-midatlantic - lists.vcfed.org

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 25 Sep '18

25 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 25 Sep '18

25 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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Re: [vcf-midatlantic] Reminder - Museum closed this weekend
by Jeffrey Brace 21 Sep '18

21 Sep '18

Yeah, I noticed the dead moths in there ;) On Fri, Sep 21, 2018 at 6:14 PM Tony Bogan via vcf-midatlantic < vcf-midatlantic(a)lists.vcfed.org> wrote: > > > > On Sep 21, 2018, at 6:12 PM, Evan Koblentz <evan(a)vcfed.org> wrote: > > > > > >>> VCF museum is closed this weekend so me, Jeff B., Corey, etc. can go > to Maker Faire. > >> I might be able to be docent Sunday afternoon. If I can I will go from > around 2 till 5 so we have a presence there. > >> > >> Tony > > > > Cool. If you go, then be sure to tell whomever's at the front desk. > > Roger that. I still need to close the door on the MOBIDIC so those > freeloaders stop coming in and dying in the case!! > Tony -- ======================================================= Jeff Brace =======================================================

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Reminder - Museum closed this weekend
by Evan Koblentz 21 Sep '18

21 Sep '18

VCF museum is closed this weekend so me, Jeff B., Corey, etc. can go to Maker Faire.

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Converting C64 from NTSC to PAL was: PAL C-64 on 1084-S?
by Herb Johnson 20 Sep '18

20 Sep '18

> I had asked many times how to convert a NSTC C64 to PAL and got many > different answers. I feel like I was sent down the wrong path. Jeff, I'm not continuing this discussion to annoy you, but to make a more general point in public. Also, maybe you'll be less frustrated if you see larger purpose in your process of resolving this conversion - you suggested one yourself, you learned the details of NTSC vs PAL and analog video. As I posted previously, solving problems isn't always about "a path" to a single solution. Not all problems are solved by doing one thing, but by doing many things. It's part of problem-solving to attempt many things. Each thing, either solves part of the problem, or aids your understanding toward a solution. And in the end, you don't just solve "a problem", you expand your knowledge and experiences. So Jeff, I think the path you followed, was mostly normal, not an effort to mislead you. In the larger discussion: some people work with vintage computers, because they enjoy "fixing things" or "getting things back into use". Sometimes repairs are a matter of necessity. And repair can be a learning opportunity. And it's fun to share repair experiences, which is what happened in this email discussion. When I start talking about "building character", that's when I've said too much. ;) Jeff, glad you've got PAL operation of your C64. Herb -- Herbert R. Johnson, New Jersey in the USA http://www.retrotechnology.com OR .net

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