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model 14 shadow meter wiring
#5

This is the first time I looked at a shadow meter circuit on the 14, and it is pretty weird. It appears to measure plate circuit current drawn by the RF amp, or RF and IF Amp or RF, IF and Convertor, depending on which schematic we look at, which I suppose is affected by AVC Bias.

The meter is in series between the plate circuit (B+ to transformer primary) of the IF amp and B+ of the RF Amp.

Since the radio is playing without the meter in place, someone replaced the meter with a wire connection, bypassing the meter.

For the meter to function and not cause the radio to cease operation, 3 things must occur:
1. The winding has to be in series and the bypass connection must be removed
2. The coil of the meter must be the correct resistance.
3. The meter must have no leakage to its frame, causing a short of B+ to ground.

Hope this helps.

"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis

Best Regards, 

MrFixr55


Messages In This Thread
model 14 shadow meter wiring - by madsowry - 10-21-2025, 05:06 PM
RE: model 14 shadow meter wiring - by KCMike - 10-21-2025, 06:13 PM
RE: model 14 shadow meter wiring - by madsowry - 10-22-2025, 09:57 PM
RE: model 14 shadow meter wiring - by Bill Bacco - 10-22-2025, 11:12 PM
RE: model 14 shadow meter wiring - by MrFixr55 - 10-23-2025, 03:54 AM
RE: model 14 shadow meter wiring - by madsowry - 10-23-2025, 07:45 PM



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