Unusual Marshall amp fault
Wond wrote:
On Sat, 03 Dec 2011 13:17:22 +0000, N_Cook wrote:
Not really detective work. My repair methodology starts (after initial
powered up assessment if appropriate, then dismantling) with a full
viewing under a x5 illuminated inspection lamp+ bulbous lens. Noting
unusual device types, large R values if no schematic, state of solder
joints, insulation, discoloured areas etc. I just saw what initially
looked like a non-cropped off wiring-end ,through the valve base tag,
ending too close to a pin 1 to pin 7, bare cross-coupling wire. Up to
then I was thinking mains transformer interwinding fault.
Physical inspection is an important part of the diagnostic process. Good
eye.
I always do a shake test, even with new computers to check for fallen out
screws, coins or other junk.
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