22 Aug
2002
22 Aug
'02
7:03 a.m.
This problem is common with lower-quality IC sockets.
Sockets that do not use the fancy machined-pin contacts have a upwards
spring-force against each pin.
Add thermal cycles, and the chips will start creeping out of the socket.
Part of the problem is mechanical creep, but oxidation is also a factor,
as the sockets that exhibit this
problem are tin-plae phosphor-bronze. Gold-clad sockets don't generally
fail this way, and the round
pin (Augat style) socket pins basically never fail.
Bob Lafleur wrote:
How many of you remember the problem of chips coming
unseated in older
computers (like the PET) and having to push all the chips down as the
equipment ages?
I've now got this problem with my Kurzweil MIDIBOARD (a 6502-based MIDI
keyboard controller). A few months ago I had to open it and reseat all
the chips. Now I have to do it again.
Does anyone know any tricks to keep this problem from occuring? I fear
I'm going to have to do this a lot now, especially with the vibrations
of playing the keys.
Thanks for any tips.
- Bob