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Has anyone tried a commercial Bias tester to check bias readings for different tubes on the Tramp?

I tried 4 different 6L6's (bias should read from 32-37mA) and got results from 75 to 80mA. With trials of 3 different 6V6's I got 39-42mA (switch in 6V6 position). The 6V6's should read from 25-35mA.

I had the 6V6/6L6 Switch in the correct position (Pin 8 to ground reads 750 ohms for 6V6 setting and 320 Ohms for the 6L6 setting).

All voltages are in range although I got 30.5 at V2 Pin 8 versus 29 VDC as shown in the spec.

This is a huge bias difference for 6L6 tubes and 6V6's are also running on the high side. Should I change the values of the two V2 cathode caps? If so, should resistances go higher or lower to get bias readings in range for 6L6 and 6V6 tubes?

Thanks - Tom

Single Ended amps (Class A) bias to 100% or more plate dissipation.

Your probably used to push pull fixed bias where you bias to ~70% max plate dissipation.

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