04-23-2022, 04:03 PM
Would you happen to have a vacuum tube volt meter or a fet input analog meter? These have a much higher input impedance and won't load the circuit down that they are connected to. Something like this could be used to monitor the AVC voltage which would give you a indication of signal level. Like a S meter.
Your VOM is more than likely about 10 or 20K ohms per volt. The VTVM or fet input meter is going to be about 10meg ohms per volt. So the latter is pretty much invisible to the circuit.
The voltage across the voice coil is going to be ac so trying measure it with your meter set on a dc input will not work... Unless you place a diode in series with it.
The other solution is to disconnect the secondly from the voice coil and connect a 2 ohm 5W resistor across the secondly.
Your VOM is more than likely about 10 or 20K ohms per volt. The VTVM or fet input meter is going to be about 10meg ohms per volt. So the latter is pretty much invisible to the circuit.
The voltage across the voice coil is going to be ac so trying measure it with your meter set on a dc input will not work... Unless you place a diode in series with it.
The other solution is to disconnect the secondly from the voice coil and connect a 2 ohm 5W resistor across the secondly.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got it!
Terry
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