Mike's PCjr Page

Now, I have a different problem. I left the computer on for about 2 hours and when I came back to it, the screen was blank. It would not ctrl-alt-delete, and when I shut it off and turned it on, it immediately beeps twice. The display is blank. The disk does not turn on. Does anyone know what I can do?

That could be any number of problems, really. I had it happen to me twice. First time, there was a wire broken in my Tandy video mod, so the video circuit wasn't starting up. Second time, I had a couple of pins on my 8284 shorted out. Best advice I can give is to open it up, take the board out, and look for anything out of the ordinary.

I think I found the problem. I saw Mike's post on the vintage computer forum and I unplugged different things. When I unplugged the 64k card on the motherboard, it started up. What can I do about this? Do I need a new 64k card?

You can either get a new 64k card, or you can replace the chips on your existing card. It's up to you.

I don't have any experience replacing chips. Is it easy? Also, I was using the 128k sidecar without the power expansion. Could that be the cause of the failure?

Replacing chips is painfully slow but perfectly feasible if you are careful. Get a good solder suction pump from your local Radio Shack along with some desoldering braid. Heat each pin until the solder is molten then suction it with the pump. Clean any residual solder with the braid, then gently wiggle the pin to loosen it. Repeat for the remaining pins. Make sure that your soldering iron is set to 15W so as not to cook the chips or lift the circuit board pads. Use a chip extractor to pull the chips out once all the pins have been loosened.
If you only have a couple of sidecars, it is unlikely that you will need an additional power supply for them. I actually have 2 parallel ports and a memory expansion sidecars and I don't use an additional power source.