• 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.

250Th single end config

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Last edited:
Just Simply. Drive it with 8b8 with IST. Baias with positive voltage. The 250th sound nice when it drowning Plate Current 100ma. Or more depend how much High voltage is Used the output transformer can calculate from its data

Regard
 
Just Simply. Drive it with 8b8 with IST. Baias with positive voltage. The 250th sound nice when it drowning Plate Current 100ma. Or more depend how much High voltage is Used the output transformer can calculate from its data

??
Not everything is simple and clear at first, although I am an experienced self-builder and costructor! Some data would be useful if you do not want to publish the scheme already.
That would be in order:
Operating parameters for 8B8 such as supply voltage, bias voltage (or cathode resistor value), plate impedance of the transformer if the excitation of the output tube is made using it and current through the excitation pentode.
Operating parameters for 250TH such as supply voltage, grid bias, plate impedance and excitation transformer gear ratio (if excitation is made with it).
There is more data that would be interesting such as transformer inductors (in Henry), transformers clean core cross sections, HV rectifier type, 250TH heating rectifier, etc.