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PostPosted: Wed Apr 13, 2005 5:45 pm 
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Joined: Wed Mar 30, 2005 3:59 pm
Posts: 23
Location: So. CA
All my preperation to do something with my AIM 65, I finally decided to get it out and apply power.

It's been sitting in the original box since about 1985. I think it was working when I packed it up, the only reason I packed it up was I got my first Mac and didn't have room on my desk for both, so the AIM got packed.

Anyway, I got out my power supply, checked it out, sure enough +5v was still +5v and +24 v was still +24v. I then unpacked the AIM, trying to be as "static sensitive" as possible, then visually inspected it for obvious problems (anti-static material stuck on pins) and then did a little re-seat of all the socketed ICs. plugged in the keybaord, connected the +5v only and applied power... Nothing, no display, nothing I checked the +5 at a TP on the board and it appeared OK.. I then checked the ICs again and appllied power again... nothing. Well, it then thought I would see what happens if I apply the +24v and +5v. Connected it up turned it on, nothing... upon turining it off the printer cycled ( think it was just an electro-mechanical thing, not control).

Well, remove power, inspect the board again, blow off any dust, gently, partly remove all the socketed ICs (not out of the sockets) in hopes that maybe if there was some oxidation it would wipe it off. Connected the +5v only and turned it on again... nothing, nada, zilch (bummer)

I don't have a scope or anything, I only have a VOM, so my testing is rather limited, I don't even know anyone who still has an o'scope.

Any ideas of what I could try?

Any ideas of a reputable repair service in So. CA? (That might fix it without charging me an arm and leg and first born son.)


Thanks for any and all replies, ideas an/or help

AndyD


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PostPosted: Thu Apr 14, 2005 8:34 am 
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Joined: Tue Mar 09, 2004 3:43 pm
Posts: 44
Location: Bristol, UK
Sorry to hear that your AIM-65 isn't working. You've already eliminated the first thing I'd have suggested, which is checking the power supplies. Tantalum capacitors often go short-circuit, and they're often across the power supplies for decoupling.

The next thing to check for is the clock, which will require an oscilloscope of some sort. Which you don't have (darn).

I doubt you'd find anyone who'd offer a commercial repair service for something as old as this. I certainly wouldn't trust a repair service, either. Too many people who've never seen any kind of computer apart from a PC, and won't have a clue what to do with a classic. Not that they'd tell you that (they'd wreck it first, then claim it's unfixable).

But you could try asking on the Classic Computer Mailing List:

http://www.classiccmp.org/

If you subscribe, read the archives and post a message, you may find someone who's both local and knowledgeable about the AIM-65.


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PostPosted: Thu Apr 14, 2005 1:22 pm 
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Joined: Sun Nov 28, 2004 3:21 pm
Posts: 14
Location: Toronto, Canada
If you can get your hands on a Digital Multimeter with built in logic probe, or even a logic probe by itself, you should be able to check for system clock and activity on address and data bus of 6502.

I really wish I had a good scope (mine was built in 1956 and only has bandwidth to 60khz). However, a lot of basic trouble shooting can be done with simple logic probe.


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PostPosted: Thu Apr 14, 2005 2:07 pm 
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Joined: Wed Mar 30, 2005 3:59 pm
Posts: 23
Location: So. CA
Hi,

Thanks for the help, I didn't subscribe yet, but I did find two recent posts concerning AIM 65 and I emailed them (hope they don't mind) so maybe I will find some more ideas that way, if not, I guess I'll subscribe and put out a plea there.

Thanks,

AndyD


coredump wrote:
Sorry to hear that your AIM-65 isn't working. You've already eliminated the first thing I'd have suggested, which is checking the power supplies. Tantalum capacitors often go short-circuit, and they're often across the power supplies for decoupling.

The next thing to check for is the clock, which will require an oscilloscope of some sort. Which you don't have (darn).

I doubt you'd find anyone who'd offer a commercial repair service for something as old as this. I certainly wouldn't trust a repair service, either. Too many people who've never seen any kind of computer apart from a PC, and won't have a clue what to do with a classic. Not that they'd tell you that (they'd wreck it first, then claim it's unfixable).

But you could try asking on the Classic Computer Mailing List:

http://www.classiccmp.org/

If you subscribe, read the archives and post a message, you may find someone who's both local and knowledgeable about the AIM-65.


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PostPosted: Thu Apr 14, 2005 2:10 pm 
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Joined: Wed Mar 30, 2005 3:59 pm
Posts: 23
Location: So. CA
Hi Brian,

Thanks for the suggestion, guess maybe I should look for an inexpensive logic probe, I didn't consider a logic probe, but it just might do the trick.

Thanks,

AndyD

Brian_Lyons wrote:
If you can get your hands on a Digital Multimeter with built in logic probe, or even a logic probe by itself, you should be able to check for system clock and activity on address and data bus of 6502.

I really wish I had a good scope (mine was built in 1956 and only has bandwidth to 60khz). However, a lot of basic trouble shooting can be done with simple logic probe.


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