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Model 650 Tone Control Question
#16

I checked the AC voltages and they all seem good but I’m getting some strange DC readings. 

The first 42 output tube, red circle is giving me approximately 120 dc on both plate and grid. I say approximately because it seems to fluctuate. I have switched the 42’s around but the readings stay similar. The other 42 output tube, green circle, is giving me 365 dc on both plate and grid. No fluctuating there! The 42 driver tube is 246 on both the plate and grid.

The 6A7 is 250 on the plate, 86 grid and 2.45 cathode, 78 IF is 261 plate, 86 pin and 1.68 cathode, the 78 RF is 122 plate, 86 grid and 2.34 cathode and the 75 is 171 on the plate. 

Hopefully this provide some needed information for those of you that are much better at troubleshooting then I am. Please feel free to comment. I don’t have much experience but I do have thick skin so any advice is appreciated.


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Messages In This Thread
Model 650 Tone Control Question - by Hamilton - 06-27-2023, 10:45 AM
RE: Model 650 Tone Control Question - by morzh - 06-27-2023, 12:11 PM
RE: Model 650 Tone Control Question - by Hamilton - 06-27-2023, 05:49 PM
RE: Model 650 Tone Control Question - by morzh - 06-27-2023, 07:26 PM
RE: Model 650 Tone Control Question - by Hamilton - 06-29-2023, 08:03 AM
RE: Model 650 Tone Control Question - by RodB - 06-29-2023, 09:09 AM
RE: Model 650 Tone Control Question - by Chas - 06-29-2023, 10:26 AM
RE: Model 650 Tone Control Question - by morzh - 06-29-2023, 10:57 AM
RE: Model 650 Tone Control Question - by Hamilton - 06-29-2023, 11:46 AM
RE: Model 650 Tone Control Question - by RodB - 06-30-2023, 08:31 AM
RE: Model 650 Tone Control Question - by Hamilton - 06-30-2023, 11:45 AM
RE: Model 650 Tone Control Question - by Hamilton - 06-30-2023, 02:07 PM
RE: Model 650 Tone Control Question - by MrFixr55 - 06-30-2023, 05:22 PM
RE: Model 650 Tone Control Question - by Hamilton - 06-30-2023, 07:57 PM
RE: Model 650 Tone Control Question - by Hamilton - 06-30-2023, 08:13 PM
Hamilton - by Hamilton - 07-03-2023, 10:13 AM
RE: Model 650 Tone Control Question - by Hamilton - 07-03-2023, 12:10 PM
RE: Model 650 Tone Control Question - by MrFixr55 - 07-03-2023, 11:25 PM
RE: Model 650 Tone Control Question - by MrFixr55 - 07-04-2023, 12:40 AM
462ron - by 462ron - 07-04-2023, 08:56 AM
Hamilton - by Hamilton - 07-04-2023, 09:54 AM
462ron - by 462ron - 07-04-2023, 10:06 AM
RE: Model 650 Tone Control Question - by Hamilton - 07-04-2023, 03:13 PM
RE: Model 650 Tone Control Question - by MrFixr55 - 07-04-2023, 04:26 PM
RE: Model 650 Tone Control Question - by MrFixr55 - 07-04-2023, 04:38 PM
RE: Model 650 Tone Control Question - by Hamilton - 07-06-2023, 08:11 AM
RE: Model 650 Tone Control Question - by MrFixr55 - 07-06-2023, 11:40 AM
RE: Model 650 Tone Control Question - by Hamilton - 07-07-2023, 07:48 AM
RE: Model 650 Tone Control Question - by Hamilton - 07-07-2023, 02:59 PM
RE: Model 650 Tone Control Question - by RodB - 07-07-2023, 03:11 PM
RE: Model 650 Tone Control Question - by MrFixr55 - 07-07-2023, 09:23 PM
RE: Model 650 Tone Control Question - by Hamilton - 07-08-2023, 09:30 AM
RE: Model 650 Tone Control Question - by MrFixr55 - 07-08-2023, 12:07 PM
RE: Model 650 Tone Control Question - by morzh - 07-08-2023, 05:32 PM
RE: Model 650 Tone Control Question - by Hamilton - 07-09-2023, 06:15 AM
RE: Model 650 Tone Control Question - by MrFixr55 - 07-09-2023, 07:55 AM
RE: Model 650 Tone Control Question - by MrFixr55 - 07-10-2023, 04:39 PM
RE: Model 650 Tone Control Question - by MrFixr55 - 07-11-2023, 09:10 PM
RE: Model 650 Tone Control Question - by Hamilton - 07-12-2023, 07:50 AM
RE: Model 650 Tone Control Question - by Hamilton - 07-12-2023, 12:20 PM
RE: Model 650 Tone Control Question - by MrFixr55 - 07-12-2023, 05:58 PM
RE: Model 650 Tone Control Question - by Hamilton - 07-12-2023, 06:46 PM
RE: Model 650 Tone Control Question - by Hamilton - 07-12-2023, 06:49 PM
RE: Model 650 Tone Control Question - by MrFixr55 - 07-13-2023, 04:13 PM
RE: Model 650 Tone Control Question - by Arran - 07-13-2023, 04:39 PM
RE: Model 650 Tone Control Question - by MrFixr55 - 07-13-2023, 05:13 PM
RE: Model 650 Tone Control Question - by MrFixr55 - 07-14-2023, 06:05 AM
RE: Model 650 Tone Control Question - by MrFixr55 - 07-14-2023, 06:25 AM



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