I’ve replaced everything regarding the cassette portion of the vic. Caps, resistors, zeners, transistors. Still can’t get it to spin the reels. Says “Press play on tape”, and then I do, and it says it’s searching. Forever. No movement. I tested continuity all the way back as far as I could, and it’s fine. I don’t get it. Doesn’t show any power being delivered to the motor when I test voltage. Changed 6522 as well, and still no go.
Thought the Vic was running like new? I did. Until I hooked up the tape drive. I send it the load command, and hit play on tape. The Vic recognizes that I hit play and starts searching. But the drive doesn’t move the tape. Checked the belt, and it’s fine. The motors just aren’t moving, and I tried it on two tape drives. Looks like a transistor bit the dust. 2SD880 in location Q1. Tried to find one at the electronics shop when in Toronto, but no luck. Going to need to order one (and hopefully a bunch of other stuff because postage will be 16x the price of a single transistor). I also need to pick up a real axial capacitor for the Vic, and take out the hobbled together radial capacitor that I shoved in there for the time being.
Decided that yesterday was the day to recap the Vic. It wasn’t in bad shape, but the big 4700uF cap was leaking and corrosion was heading on down towards the motherboard. That’s just not cool.
Here’s the insides of a 2-pin Vic-20. It just uses a 10VAC power supply instead of the newer versions that use a DIN connector that supplies 5VDC and 9VAC.
Here’s the problem child:
Everything else was replaced since it was opened up, and I had the caps. There aren’t many to replace either, I think around 7?
I did the 128 this morning, but didn’t take and pictures. There are a fair bit more to change, but not bad. Maybe an hour or so.
Picked it up on a whim, for dirt cheap. Came as-is, untested. With a 1541, an Atari 2600 Jr. (why, I don’t know, but whatever, I love the 2600). 1541 needs to be cleaned with holy water, as it’s acting a little odd. I already have 8 or 9 of them, so it’s not that important to fix right now.
Needless to say, it works!
It has some problems. Missing a key, a spring, and the plungers are broken. I managed to fix the tab key (needed a spring) so that it didn’t constantly tab the cursor when the machine was on. The missing key (ALT) is long gone, and I was told these keys are as rare as hen’s teeth. So It’ll probably be missing for a really long time.
Last problem (so far) and the biggest: They keyboard matrix was acting weird. I tore the keyboard apart checking continuity, swapped the 6526 chips around to rule those out. After more tracing, I found this:
Good times. The faint blue circle is the problem child. It’s not allowing EMI21 to connect with pin 3 of the CIA. Someone recommended a silver conductive pen to fix, but they’re $70 and don’t last. Another was a fiberglass pen to scrap it down to the copper and solder a jumper wire in there. I’m going my own route, and soldering a jumper on the underside of the board. That way I can’t hurt anything (like the socket).
Just how it left the factory. I haven’t cleaned this at all!
I do see one major issue that needs to be addressed quickly. I had already bought replacement capacitors before I opened the machine, and now I’m glad that I did. I don’t see any damage to the board, but this one needs to go as soon as possible before bad things happen. Of course, this is the only one that I couldn’t get at the local electronics shop, so time to order one.
Over on the left is our original C64. The right, our original Vic-20. Both currently work (after being stored for 20+ years in the attic), but are in need of a really good cleaning.
The Amiga 500 I scored last year (my first Amiga — FINALLY!). Came with 1084 monitor, external floppy, printer, and a few disks.
The Amiga 600 I picked up before Christmas of last year. Currently has an IDE to SD card adapter, 10bt ethernet in the PCMCIA port, and a serial connection to another host (my BBS) so that I can “dial” out. The other 64s were rescued at various times. I was amazed that I got the silver label 64 for $10! Everything works, again just needs a cleaning. Behind the 64 is one of Ray Carlsen’s power supplies. It’ll run a 64, 128, or Amiga (one at a time). Nice clean power instead of dealing with those ticking time bomb power supplies that came with the machine originally. Worth every penny.
I’ll get more listed as I go.
Just my first entry. Nothing fancy yet. Trying to figure this out.