8 replies to this topic

[Keatah]

That's right folks. My ancient Apple //e from 1982 has now died. I went to turn it on and got some random garbage onscreen. I got strange text at the top, and about 15 or so random characters across the screen here and there.

It responds to the keyboard, and resets, and lets me type something in (displays normal characters here). And sometimes accepts the commands, and sometimes not. Shit like HGR and HGR2 and TEXT work, but don't return the command prompt ]. Dropping it on the floor and reseating chips hasn't helped, neither has putting it in the oven & freezer.

This is my special //e from the BBS days, right as warez kicked into high gear. It ran one of the A.E. lines and was a central distro hub when I "graduated" to running BBS software. This is the one we'd put on RadioFlyer wagon from time to time and bring the warez TO YOU!

And it would be devastating to lose it. So without further ado I'm open to suggestions as to how to fix this little guy.

[JamesD]

Don't drop it, that was the III. Oven and freezer? Who have you been listening to?

It could be bad RAM. Try feeling if one is hot but I doubt it will be since things are partially working.
Try removing cards and see if things change. (which you've probably already done)
Manually press down on the chips to see if that helps.
A bad ROM might let the system partially work.
I don't think a flaky power supply would do that.
Look at the capacitors to see if any look bad. A bad cap might do that.
Applefritter forums might have more suggestions.

I have a IIe in storage I tested and haven't used since. I think it's an enhanced IIe (1985) but you might be able to use parts or just swap the board if you can't figure it out.

[Keatah]

ok, no cards installed. Same deal.
Power supply checks fine. good ripple.
I figured the oven and freezer would contract and expand the metal "stuff" inside the chips. Same deal.
Caps look good. I know a bad cap on sight, fixed enough of that stuff in PC's..
I reseated each chip, no change.

Things that I've experienced failing on II series in the past was indeed the ram, so I shall start there.
This //e was often left outside in the car overnight in sub-zero winters. And it was run up in the attic with no A/C and a full complement of cards. So it's no stranger to temperature extremes.

I'll crosspost this on Applefritter and see what I get there..

[madmax2069]

Can't you piggyback the ram chips to basically diagnose them ? it defiantly sounds something like a ram or rom issue. I have also seen issues with the chip sockets themselves. I do hope that you find out what the issue is, good luck.

[Keatah]

I'll begin there, first with the ram, then the roms. Hopefully it's ram, because I've got some spare 4164's someplace here.

I doubt it's the cpu, or keyboard stuff, or other supporting chips. This is beginning to smell more and more like ram failure.

Edited by Keatah, Sat Jan 21, 2012 6:37 AM.

[Keatah]

And boy did it sure stink of ram failure. Success! I ran the built-in diagnostics and was getting inconsistent bad ram, it would say things like:

RAM 0 0 1 0 0 0 0 0, or sometimes it would pass and say system ok, but with some random characters here and there.. Mostly it would pass. So I swapped out the "1" ramchip and sure enough it worked! I put the faulty one back in and checked the data/address lines, one of which was lazy or so it seemed. Swapped it out again, and it passes consistently and powers up just fine.

Edited by Keatah, Sun Jan 22, 2012 1:33 AM.

[Ransom]

Awesome! I'm glad you were able to fix it.

[JamesD]

Glad to hear you could fix it.

[Keatah]

That's the nice thing about vintage computers. When they do break down, parts readily available and can be swapped in and out in a jiffy. Soldered or socketed, it's about the same. And it can be fun to fix them, from time to time.