Thread: "Fuzzy" FM
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Old 8th May 2011, 8:52 pm   #14
Dillen_de
Tetrode
 
Join Date: Jun 2007
Location: Copenhagen, Denmark
Posts: 62
Default Re: "Fuzzy" FM

I chose to pull forward this older thread because I have a fault that seems to be very similar.
FM sounds as if the set was tuned just off center.
The set has ECC85 / ECH81 / EF89 / EBF89 / (2x OA79) / ECL82
New electrolytic cap in the discriminator and I tried adjusting the pri/sec discriminator coils but
the distortion remains.
It's not a lot, just enough to be annoying.

Tape input is perfectly clean on the scope, so the output stage is fine.
On AM it whistles more than usual, I get more whistles than stations (if any).
Any ideas ?

Martin
Dillen_de is offline