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Low volume on 645 console w/P-P 42's
#2

Hi Vinton, and welcome!

You did check continuity of audio interstage transformer (52), correct?

Check the plate voltage of the Type 85 (should be 82 volts), and plate and screen voltages of the two Type 42 outputs. It wouldn't hurt to check the output transformer (55) for continuity also, if you have not yet done so.

Does your radio have the correct speaker? The speaker field is only 435 ohms in this model.

The audio level should be quite listenable (i.e. decent volume) even with only one Type 42 operating. But do remove the inoperative Type 42 before proceeding further.

I doubt it is a coil problem, since each band uses separate windings instead of multi-tapped coils.

Also check the AVC circuit; make sure resistors and capacitors in the AVC line were reconnected properly.

--
Ron Ramirez
Ferdinand IN


Messages In This Thread
Low volume on 645 console w/P-P 42's - by Guest - 11-20-2007, 07:53 PM
[No subject] - by Ron Ramirez - 11-21-2007, 09:08 PM



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