Epic vintage computer repairs

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Jubatian
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Epic vintage computer repairs

Post by Jubatian »

Just a bit of interesting stuff I stumbled upon.

A quite impressive work on bringing back a Commodore PET to life:
http://www.8bit-homecomputermuseum.at/r ... uepet.html

There are many others on the site. Interestingly the site is apparently German (Austria), however some of the repair articles are in English. There are some computers there I barely even knew about.

Well, any experience alike? I guess many of you playing around with the hardware aspect of Uzebox also have some such old 8 bits which you might have tampered with (for me, nothing much: I have a Commodore 64 and an Enterprise 128K, for the latter I built a hack-job of Atari joystick from a few microswitches and a plastic sour cream container, and wired a 9 pin connector to the keyboard matrix connector to replace the dead stick, at least until I could acquire a replacement keyfoil... since then with the C64 I also got two proper Atari sticks).
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D3thAdd3r
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Re: Epic vintage computer repairs

Post by D3thAdd3r »

Cool, if you actually buy it broken and restore it that particular machine has to mean a lot more to you. I ebay'ed an Atari 1040ST not realizing it had a VGA mod that only supports the high res monochrome, which I don't want, now it lays in pieces until I ever get around to making it work with RGB...ugh more research :lol:

I came across a nice deal on a C64(c) that spent ~20 years in an attic with all the fixings, different modems, everything mint and in box AS-IS/Untested so took the chance. Only the datassette isn't working so I need to figure that out. Need to spend some more time with that thing and try to get on Quantum Link Reloaded...maybe talk to an Uzebox with it over the net!
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uze6666
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Re: Epic vintage computer repairs

Post by uze6666 »

Very cool rebuild. I'm pretty sure I would have had his patience, so kudos. :)

I have an old Tandy1000 in a box somewhere I should try and plug it in someday. I have tons of basic programs I made for that thing back then that I'd like to see.
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Jubatian
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Re: Epic vintage computer repairs

Post by Jubatian »

I am always a bit jealous for those folks who had those in their childhood. I didn't knew anything about the 8 bit era until I drifted towards it from coding Qbasic and likes. Here I still remember we borrowed computers for the winter holidays, already IBM PC's, with amber monochrome monitors, and played Grand Prix Circuit on it, trying to beat each other in time races.

Well, for the Enterprise I actually recapped the cassette deck, but didn't quite succeed with it. Playback is all nice, but recording is wobbly, producing amplitude swings. When recording audio it is not that noticeable, but it is unsuitable for writing programs, I could only once get it successfully writing a loader on a tape. On the other hand the nice thing with the Ep is that it has standard audio jacks, so you can play the "tape" (a wav file) from a PC directly.

(Huh, I didn't even remember I had this image on my site. You can see the "kludgestick" on the right bottom, the butt of a cream sour container, the 'X' is where the microswitch for "fire" was placed)

For the C64 I actually use an XE1541 cable, and an old Siemens Nixdorf laptop. But not for writing to floppies, there is a program called 64HDD which can emulate the 1541. Incomplete, it doesn't realize the 6502 inside, but with connecting the Siemens Nixdorf via a serial nullmodem cable to my main PC, I could try out results of my coding directly on the real thing in a fairly simple manner.

But now I have that nice old PAL television which I had for these broken... Probably not the tube, but it is beyond my capabilities (and in that lodging I just have no room for doing any serious repair attempt). Of course the mini TV for the Uzebox is there, but that old thing had a way more pleasant image.
portets
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Re: Epic vintage computer repairs

Post by portets »

Wow, this thread is really relevant to me!

My first computer was a Tandy1000 RSX, but with an Intel 386sx and Windows 3.11. I've also been jealous of people that grew up with 8-bit computers and BASIC command prompts. I would've learned to code a lot younger if I had that.

So I got a Commodore VIC-20(between a PET and C64). But after a couple weeks it developed similar graphic corruption to that PET Jubation linked. I think I narrowed it down to the Character ROM, but I think that link might help a bit. Thanks!

And D3thAdd3r, you can use any cassette player as a datasette or even play cassette rips as audio files from a phone, etc. with just a transistor. But a real working datasette is always cooler. ;)
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D3thAdd3r
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Re: Epic vintage computer repairs

Post by D3thAdd3r »

portets wrote:But a real working datasette is always cooler.
Yes the way they did these things was really clever, I can really appreciate it. They have some great SD solutions for many of these machines too which I plan to get to save wear and tear on mechanical parts in the long run.
Jubatian wrote: (Huh, I didn't even remember I had this image on my site. You can see the "kludgestick" on the right bottom, the butt of a cream sour container, the 'X' is where the microswitch for "fire" was placed)
That is very cool, those are rare too only 80,000 ever made. I've never seen one of those show up on ebay during my extensive searches for my collecting habit. Hold on to that thing! Very nice artwork on your site BTW.
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Jubatian
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Re: Epic vintage computer repairs

Post by Jubatian »

D3thAdd3r wrote:I've never seen one of those show up on ebay during my extensive searches for my collecting habit.
A lot of these machines ended up in Hungary, we even have a clone of the 64K variant (Videoton TV Computer). It is relatively common here, so if interested, I could get you one (there is a 128K one up now on a Hungarian auction site). They usually sell for around 80-100 dollars worth of Hungarian currency, and I even have a spare new keyfoil (I bought two when I replaced that in mine, those sell for around $30, even now I see two up).

A problem with the machine though is that its video output capabilities aren't really friendly for today's technologies. It has a RF output (PAL signal), and an RGB output which I had seen being used for Scart, and I also had seen mods which could get the machine producing PAL composite signal. Right now I have nothing to plug my own EP in (as the old TV broke).
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D3thAdd3r
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Re: Epic vintage computer repairs

Post by D3thAdd3r »

@Jubatian - I'd like to get one and depending on what shipping troubles will be, I might take you up on that offer. I have so far had great luck with a cheap RGB SCART->HDMI 1080 upscaler that renders PAL 50hz beautifully on my NTSC 60hz for the systems I have tried. It is supposed to work great for PAL composite over SCART as well but I have not specifically tested that out.
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Jubatian
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Re: Epic vintage computer repairs

Post by Jubatian »

OK, I dropped a PM with details. The EP has an RGB output (a card-edge connector) for which a Scart plug can be designed (maybe only needing a few resistors). The card-edge connector might be an obstacle (it is not easy to get a suitable plug for that). I wish if I had something, but my 4:3 monitor accepts only VGA or DVI (while it would be a long way better for retro stuff than 16:9), and it seems like there is nothing which could cross this gap, and televisions with suitable connectivity (even if I wanted to afford one) are ginormous for the crammed place I live in. To get color PAL composite out from the Enterprise, it is necessary to hack around within the machine.
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