What's the proper voltages to run a 6V6 and 5751 in my EVJ?

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brewdude
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What's the proper voltages to run a 6V6 and 5751 in my EVJ?

Post by brewdude »

I just completed installing one of Ken's loaded fender'ish octal turretbords, & the Heyboer OT in my Epiphone Valve Junior Combo. I did add a few things. First a fuse holder. Next a stand by switch. Then a switch to remove the NFB and add a 2.2k in parrellel to the stock 1.5k R9 (for a total of 891R) along with a 1uf cap, finally another switch to add a 2.2k and 2.2uf in parallel to R8.

Can any one tell me what voltages I should want to observe at the various locations. I have a 6V6, and a 5751 tube. I am currently reading the following voltages:

my wall voltage is 124V
B1 = 304V
B2 = 271V
B3 = 251V
6V6 pin 3 = 290V
6V6 pin 4 = 266V
6V6 pin 8 = 13.0V
5751 pin 1 = 151V
5751 pin 6 = 149V

I think these numbers seem low. However, I'm not sure how to interpret them.
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tunghaichuan
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Re: What's the proper voltages to run a 6V6 and 5751 in my E

Post by tunghaichuan »

What value do you have for R10. On the stock amp this resistor decouples C6 from C9.

What is the value of your cathode bias resistor on the 6V6?


brewdude wrote:I just completed installing one of Ken's loaded fender'ish octal turretbords, & the Heyboer OT in my Epiphone Valve Junior Combo. I did add a few things. First a fuse holder. Next a stand by switch. Then a switch to remove the NFB and add a 2.2k in parrellel to the stock 1.5k R9 (for a total of 891R) along with a 1uf cap, finally another switch to add a 2.2k and 2.2uf in parallel to R8.

Can any one tell me what voltages I should want to observe at the various locations. I have a 6V6, and a 5751 tube. I am currently reading the following voltages:

my wall voltage is 124V
B1 = 304V
B2 = 271V
B3 = 251V
6V6 pin 3 = 290V
6V6 pin 4 = 266V
6V6 pin 8 = 13.0V
5751 pin 1 = 151V
5751 pin 6 = 149V

I think these numbers seem low. However, I'm not sure how to interpret them.
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brewdude
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Re: What's the proper voltages to run a 6V6 and 5751 in my E

Post by brewdude »

[quote="tunghaichuan"]What value do you have for R10. On the stock amp this resistor decouples C6 from C9.

What is the value of your cathode bias resistor on the 6V6?



R10 = 1k 3W
R14 = 240R 2W
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Manoteal
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Voltages

Post by Manoteal »

It looks like you can safely reduce R10 to bring your voltage up to about 325-350 for the plate of the 6V6. THe 1K R10 is to reduce the voltage for the EL84 which wants 300 volts MAX on it in SE designs.
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