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Old 03-06-2019, 01:28 PM
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DavGoodlin DavGoodlin is offline
Motorola Minion
 
Join Date: Aug 2011
Location: near Strasburg PA
Posts: 3,411
The damaged WW resistor I replaced with a 1-watt 390 ohm and the voltage on the 6Q7cathode is exactly right at 2.5. Other voltages agree with Riders, so we're done with resistors.

This is a little guy not a big-sound console, so I tried swapping 6K7 for 6U7 and a metal 6Q7, (original ST tubes had tested borderline) without much improvement. Broadcast reception fair, even with a 10' lamp cord antenna. The SW band even pulls in something with no antenna attached, odd. It needs an alignment just to make it incrementally better if nothing else. Next step is alignment using a Hickok 277x.

The Riders IF alignment procedure from Crosley, no doubt is a bit different than what I'm used to. You connect the generator at 455 kHz to the 6A8 grid via .02 uf cap, but the meter goes across the OPT primary "with a .1 mf cap in series to prevent meter damage from DC" Also odd, not a ac vtvm across the voice coil??
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