Thread: Defiant MSH902
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Old 31st Dec 2019, 4:02 pm   #21
Beardyman
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Join Date: Jan 2018
Location: Portsmouth, Hampshire, UK.
Posts: 428
Default Defiant MSH902 addendum

Having completed this restoration some time earlier this year I thought I would fire up the radio over the Christmas period just to make sure everything was ok. It was, for about 20-30 minutes, then gradually started to lose the bass notes & grow quieter. This was something I thought I had fixed previously but obviously I hadn't!?! As this set doesn't have any circuit diagrams available (apart from my own hand written ones) & dozens of photos I took prior to any work being carried out I thought I'd spend an hour or two correllating the two. It wasn't unitl I had the chassis out of the case (again) that I was idly prodding around the resistors attached to the FC4 valve that I found a dodgy reading. There was supposed to be a 500K strapped across pins 2 & 6 (g1 & k), mine was reading 50K! This was a case of mistaken identiity, entriely my fault but a quick glance & it "looks" like a 510K. The body is painted a brick red & the gold tolerance band looks yellow under anything but a bright white light. Needless to say the orange band is nearly invisible against the body. I changed it for the correct value & now the set is booming nicely & has been for well over 3 hours, looks like the FC4 survived. Tough things these valves!
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