Fine tuning homebrew grid-driven 2x 4cx300 amp.
Plate current meter is accurate now .
Specified ZSAC for plate voltage 1500 and up is 100mA. With 2 tubes I should see 200mA.
Bias voltage adjustment can reduce zsac by raising bias voltage for a zsac of 230mA which is still too high.
My memory of Triodes is that correct zsac coincides with correct Bias voltage.
Does tube quality factor into this? Currently, I'm running my worst set of tubes. OK, I'll swap in a set of different 300y's and re-post later today.
Plate current meter is accurate now .
Specified ZSAC for plate voltage 1500 and up is 100mA. With 2 tubes I should see 200mA.
Bias voltage adjustment can reduce zsac by raising bias voltage for a zsac of 230mA which is still too high.
My memory of Triodes is that correct zsac coincides with correct Bias voltage.
Does tube quality factor into this? Currently, I'm running my worst set of tubes. OK, I'll swap in a set of different 300y's and re-post later today.
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