• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Leak stereo20

Do you have the old switch? If you do, note how many solder points are on it. Switches are designated by "Pole" and "Throw" and/or "Center off", or "Momentary Contact".
The most simple switch is a single pole, single throw with just two connection points...the shorthand is SPST or an On/Off switch. Other types typically go up to six connection points OR DPDT .....standing for Dual pole, Dual throw. Several other types exist but these are the most common with variations in-between as in SPST, SPDT, DPST, DPDT.....
Switches are designated with voltage and current ratings. The Voltage rating is the insulation value, the current rating in Amps is how much the contacts can stand the heat and arcing across these contacts...sometimes "they" refer to a "Contact" rating. A switch for your amp should typically read something like 250VAC 6A....or 250 Volts AC @ Six amps.

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When the Dual throw switches are used, each pole is isolated from the other, further the center terminals are "common".


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