10W Amplifier with 6 tuber (T492E)

We found this 6-tube amplifier in a 1947 publication. It is a Public Address amplifier with excellent performance using triodes on the output.

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Transformerless Power Supply (CB16592E)
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Thermostatic relay (CB21285E)
We found this circuit in an old QST magazine. The circuit is powered according to the thermostatic relay...
Field Strength Meter (CB22329E)
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