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Chuck[_17_] Chuck[_17_] is offline
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Default Adcom GTP-450 turns itself off or the cpu locks up.

Allyn Oldfield wrote:
On Jun 15, 5:50 am, Chuck


On Mon, 07 Jun 2010 16:42:13 -0500, Chuck wrote:
Hello.


I used to work for an Adcom warranty station and remember this was a
common problem but I can't recall what the cure is. If anyone has a
solution I'd really appreciate it. Thanks. Chuck


The problem turned out to be conductive glue on the ribbon cable from
the on-standby switch to the upc board. It wasn't visible from the
top of the unit. I found a pin out of the upc and noticed unusual
activity on the key lines. This activity ceased and the unit
functioned properly when the cable from the switch was detached at
the
upc board. When I removed the switch from the circuit board, I
noticed a wisp of conductive glue at the cable end. Once the glue
was
removed, the unit functioned normally. Chuck


Hi

Thanks for posting this thread- I just fixed a similar problem with my
adcom GTP-450, I initially thought power supply caps, but after
replacing several of the smaller caps and all the regulator output
caps I googled and found this. Eventually it turned out to be the
power switch itself in my case. A momentary power switch from an old
ATX computer case had the correct stem for the button, and the wires
from the ATX switch replace the factory ribbon cable. I unsoldered the
old switch, and held the new switch in place with some epoxy resin and
a couple of screws- good as new!

Cheers
Allyn


Glad to have helped. Chuck