SET EL34 fixed bias

76.184.100.105

Posted on July 20, 2014 at 13:32:35

I wanted to try fixed bias on a SET EL34. Does anyone have a schematic? I have made the negative bias supply circuit but am not quite sure how to implement.

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RE: SET EL34 fixed bias

Chip647

15:33:28 07/20/14

3

RE: SET EL34 fixed bias

backendloaded

17:42:49 07/20/14

2

RE: SET EL34 fixed bias

Chip647

05:00:35 07/21/14

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RE: SET EL34 fixed bias

Chip647

15:33:28 07/20/14

3

RE: SET EL34 fixed bias

backendloaded

17:42:49 07/20/14

2

RE: SET EL34 fixed bias

Chip647

05:00:35 07/21/14

RE: SET EL34 fixed bias

backendloaded

06:03:27 07/21/14

RE: SET EL34 fixed bias, posted on July 20, 2014 at 15:33:28

Chip647
Audiophile

Posts: 2649
Location: The South
Joined: December 24, 2012

Ground the cathode through a 10 ohm resistor to measure current. Attach the negative supply though a 100K resistor right after the coupling cap.

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RE: SET EL34 fixed bias, posted on July 20, 2014 at 17:42:49
backendloaded	Thank you very much for the info. I notice two caps between the B+ and the bias voltage. Do you have a value for these?

RE: SET EL34 fixed bias, posted on July 21, 2014 at 05:00:35
Chip647 Audiophile Posts: 2649 Location: The South Joined: December 24, 2012	Those "caps" just indicate that there is a power supply, positive for the B+, and negative for the bias supply.

RE: SET EL34 fixed bias, posted on July 21, 2014 at 06:03:27
backendloaded	It is up and running. I like it a lot better than Cathode bias. I appreciate your help.

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SET EL34 fixed bias

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