From normal use, not from tinkering etc. Loss of one radio channel on a Beocenter 4000 due to internal o/c 50mH coil in an output low pass "transformer" 12x12x15mm. I don't remember coming across a failed AF/IF/RF coil before. Very fine wire , 240R/50mH , presumably part of the story.
-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on
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