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Model 89 RF stage
#4

Well I wound up changing out my 75 detector/1st audio/AVC and it cleaned up the hiss nicely plus weak stations come in much better.  On the tube tester, the old 75 tested good but I noticed an significant imbalance in the diode plate readings with one much weaker than the other.  The new 75 has almost identical readings so I'm thinking is was somehow messing up the AVC line back to the RF and IF stages.  Best to have a few spares to swap around.

***********
Dave Thomas
Coatesville, PA


Messages In This Thread
Model 89 RF stage - by RadioDR401 - 06-10-2017, 03:49 PM
RE: Model 89 RF stage - by Radioroslyn - 06-10-2017, 09:03 PM
RE: Model 89 RF stage - by RadioDR401 - 06-11-2017, 05:38 PM
RE: Model 89 RF stage - by RadioDR401 - 06-17-2017, 08:32 PM
RE: Model 89 RF stage - by Radioroslyn - 06-17-2017, 09:24 PM
RE: Model 89 RF stage - by RadioDR401 - 07-17-2017, 05:55 PM



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