06-13-2012, 08:29 AM
Hi guys: Just new to this site. I have a model 86 which is a mantle am/fm radio from ~1949. it's not the earlier unit from the 20's. I have repaired it and it works, sorta! Fm is extremely distorted and an attempt to align it fails at the ratio detector secondary trimmer. There is no effect in adjusting the coil slug. No null no nothing. Just very distorted. I would suspect an open cap across the secondary but the schematic shows none. Another weird thing. I get no audio unless I remove the 2mf cap in the detector! (new cap=no improvement) The 19c8 tests ok and swapping with another one makes no change. Anyone with any ideas? It would be greatly appreciated. This is not the most sophisticated radio and rather lo-fi but it belongs to a friend and I would not like to let her down. Thanks