Re: Apple ][+ gravely ill - seeking assistance :(

N.N. Thayer wrote:
On Jun 17, 11:00 am, "Bill Garber" <willy4...@xxxxxxxxxxx> wrote:

Did you happen to look at all of the solder joints? A cold, or cracked
solder joint can cause major problems, even if the chips are all good.
Also, if the pins inside any sockets are spread, or pushed down, then
the pins on the chips may not make contact.


I did - as far as I could tell, they were all intact.

Two other possibilities for "flaky" operation:

1) A broken lead on 0.1uF bypass capacitor (usually near a socket
that has had some exercise with removals and insertions). The
one near the CPU is particularly critical.

2) A crack in a PCB trace (unusual for Apple PCBs, but possible).
This will often be evidenced by pressure on the board near the
crack causing failure (as with a bad solder joint).

-michael

AppleCrate: An Apple II "blade server"!
Home page: http://members.aol.com/MJMahon/

"The wastebasket is our most important design
tool--and it's seriously underused."
.

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