Everyone has given Woody some good things to check. On almost any rig
repair, it is a good idea to do things suggested like first check for
loose connections by unplugging and replugging all boards, connectors,
jumpers, etc. one at a time. (Power off of course). That would be a
good time for the DeOxit treatments. Loosening and retightening any
screws that ground things is included in this first check procedure.
You may, along the way, fix the problem by any one of these steps.
Inspection of solder joints should begin at the entry of the power lead
to the rig, the fuse holder, etc. Also, check the high power stages
first, and ones that might run warm. So finals, driver, power
regulator ICs, transistors, etc. would be prime, as would filter
capacitor connections. Use a magnifier of at least 3X and a strong
light. Once you complete the first inspections and nothing has started
to make it work, you go to the more detailed inspection in some logical
order, like follow from the antenna connector on into the path of
signals. Don't overlook the chassis mounted connectors. Many a cold
solder joint has been found on a back side of a coax connector or
similar. If there are any back panel jumper plugs that normal thru
power or signals, check inside those for bad connections.
Good Luck,
Stuart Rohre
K5KVH
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