Mighty Monarch of The Air

[earlyfilm]

vts1134,

While it is possible that some component in the set has failed, you seem to have followed a logical step-by-step trouble shooting path and you have not located the problem. Let's do a little thinking out side of the box.

1) Is the variac that you are using an old fashion one with an autoformer and a mechanical slider in it?

1a) If yes, have you checked the output voltage with a different volt meter? It is possible that the built-in volt meter is off.

1aa) If yes and the meter is not correctly reading, check the variac wiring to confirm that both the meter and the output are connected to the same output taps because many autoformers have multiple taps and can we wired to either increase or decrease range of the output voltage.

1b) If the variac is a modern solid state unit designed for lamp dimming, then the non-sine wave output will cause a normal AC voltmeter to read incorrectly. (Only an iron vane meter can correctly read the peak-clipped output from one of those.)

2) Does your variac, or your service bench, have a constant-voltage transformer in it?

2a) If yes, then the non-sine wave output of that transformer will cause a normal AC voltmeter to read incorrectly. (Only an iron vane meter can correctly read the peak-clipped output.)

Originally Posted by vts1134

In the meantime my question du jour has to do with L18, the horizontal size control. The schematic calls for an impedance of 35 ohms. It doesn't give it a value range though. Would 35 ohms be on the high side, or low side? The reason I ask is that my horizontal size control is at 3 ohms and spins, but does not adjust in impedance. Obviously broken . . . . .

3) Are you confusing impedance with resistance? If not, how are you checking inductance?

4) As a final suggestion, since Pittsburgh is a large city, see if you can find a volunteer who is familiar with 60 year old electronic circuits to double check both the value and wiring of your replacement capacitors.


It has been my experience that I can almost never find an error that that I made while repairing a circuit.

Please understand, in my 60 year involvement with electronic circuits, I have been tripped up by each of the above mentioned items.

James.