trick for intermittent circuitry--

[eshort]

aquired a Grundig Portable satellit 500 radio which would play fine for about 5 minutes and then quit( quit defined as loss of signal so only "white noise is heard).

Removed radio chassis and used a small hair dryer to direct heat (carefully) at various sections of the curcuitboard.

Sure enough--this showed intermittent circuit in the "front end" (RF amplifier).

Used a cone (fashioned out of a small piece of thin cardboard) to narrow the beam of heat to try and isolate the exact component opening..

then-brought out the soldering iron and redid several solder joints.

radio workiong fine so far--we'll see if this fix lasts.

ps--a can of compressed air can be used to cool the heating to further help isolate the bad compoinent(s)...after the hair dryer heating...ie..see if the intermittency can be repeated by colling etc,l

moral= if u encounter intermittentency in electrical curcuits-try carefully heating sections of the board with a hair dryer and see if this has any effect--if does--u can isolate further by narrowing the cone of heat with a piece of cardboard.