Re: Zip GSX

[supertimer@aol.com (Supertimer)]

cptfa@aol.com (CPT FA) wrote:

>Sorry for the lack of background, I have a Zip GSX v1.02 card (7MHz [WDC
>W65C816PL-7] w/32K Cache) that had a soldered oscillator (28.322 MHz).  As the
>upgrade FAQ suggested, I desoldered the oscillator and attempted to replace it
>with a 14 pin socket so I could try several variations of faster oscillators
to
>try and improve the 7MHz speed to the 10MHz range without having to find the
>new 14-16 MHz CPU chip.  I don't believe that I was able to get the new socket
>to hold enough solder to make the connection.  I think that may be my problem.

>What I may need is a good "solder slinger" with the capability to test the
card
>after repair to see if it will boot up.  That has been the extent of my
upgrade
>attempt.  Prior to my removing the Zip card everything was functioning just
>fine (My new motto; If its not broke, don't break it!).  Any suggestions? 
>Thanks.

Yikes!  Do you still have the original oscillator?  It could be that the
oscillators you tried are too fast.  Try the original in the socket and
see if it works.

If not, the card may have been damaged during the desoldering of
the original oscillator.  The pins of the oscillator or the socket
make electrical contact with the card at one point only, the metal
ring around the hole.  This ring makes contact with both the solder
(and thus the pin of the oscillator or the socket) and the trace
(the wiring of the card).  Do you remember if a metal ring from any
of the four holes came off during desoldering of the oscillator?  If
so, you would have found the cause of the problem.  If the metal
ring is missing, soldering the pins in the holes would just hold
them to the card without any electrical contact.

The reason I suspect this is because I almost lifted a ring or
two off while desoldering on circuit boards.

I'm not sure how to repair such a damage.  The good news is
that the electronics on the card should be fine.  You just have
to find someone who knows how to restore electrical contact
between the socket pins and the traces.  Such a person
might do it by soldering wires from the socket pins to the
nearest junction of the respective traces.  That's just a guess
on my part based on the hacks I've seen underneath some
ROM 01 motherboards.  Apparently, some of Apple's IIGS
ROM 01 boards had a jumper wire soldered between two
such junctions on the bottom side.