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Model 89 RF stage
#1

I just finished restoring a model 89B code 123 that I got from a friend.  It was in pretty bad shape so I don't know how well or even if it played before the restoration.  I fired it up and did an alignment after which I am able to receive a few stations across the broadcast band.  Except for one station that is 3 only miles away, the others (about 30 miles away) are really weak, touchy to tune and hissy (white noise not interference).  The audio is not garbled and actually sounds pretty good except for the hiss.  I moved the antenna lead from the input clip to the grid cap on the 44 RF amp and the weak stations sound about the same.  Then I moved it to the 77 oscillator and again the weak stations sound about the same.  I'm wondering if there is a way to see if the RF stage is actually amplifying the signals since it seems like the set would work about the same without it.  I did rewind the tickler and changed the 36 to a 77 which seems to be working great.  All of the RF stage voltages are really close to spec and the coils all have continuity and resistances close to the values on the schematic.

***********
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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