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Bias on SovtekEL34 WXT

4/13/2000 7:16 PM
Lars	Bias on SovtekEL34 WXT I have a Bluesbraker (JTM45 Combo). How high can I set the bias with Sovtek EL34WXT ? The voltage on pin 3 is 407 Volt. I have it bias at 35mA now (Messaured in mV over 1ohm to ground from pin 1 and 8). Before I had Sovtek 6L6 tubes bias to 32mA, when I change the tubes I change the 470ohm/5watt resistor to 1kohm/5watt and change the bias resitor from 68Kohm to 51Kohm. The Heater voltage decreased from 6.4Volt to 6.1 Volt with EL34 so I took out the tube for the Tremolo, I never used it anyway, and the heater voltage raised to 6,2 volt. I think the trafo has no problem with the new tubes.

4/13/2000 7:16 PM

Lars

Bias on SovtekEL34 WXT

I have a Bluesbraker (JTM45 Combo). How high can I set the bias with Sovtek EL34WXT ?
The voltage on pin 3 is 407 Volt. I have it bias at 35mA now (Messaured in mV over 1ohm to ground from pin 1 and 8).
Before I had Sovtek 6L6 tubes bias to 32mA, when I change the tubes I change the 470ohm/5watt resistor to 1kohm/5watt and change the bias resitor from 68Kohm to 51Kohm.
The Heater voltage decreased from 6.4Volt to 6.1 Volt with EL34 so I took out the tube for the Tremolo, I never used it anyway, and the heater voltage raised to 6,2 volt. I think the trafo has no problem with the new tubes.

Replies:

Troy Wow, 407Vdc on the plates. I didn'... -- 4/13/2000 7:28 PM
A.S I think you could have left the tre... -- 4/13/2000 7:39 PM