Hi..i am a new user here. As per my knowledge If your meter is auto-ranging, it should find the correct scale on it's own as long as you are set to DC voltage. Two things that could also cause a problem are weak batteries in your meter and the possibility that you used a 10 ohm resistor on each socket and not a 1 ohm. The 10 ohm would still allow you to check your bias but your actual reading would be off by a factor of ten.
one-stop pcb
NEED HELP! 50w kit
Moderator: VelvetGeorge
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Re: NEED HELP! 50w kit
Last edited by NoellEagan on Sun Mar 13, 2022 4:47 pm, edited 2 times in total.
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Re: NEED HELP! 50w kit
Thanks for the post, but I definitely said 1ohm in the first post. As I stated already, the bias range resistor Just wasn’t the correct value. The kit came with a 27k, but I needed a 33 or 47k to get the bias voltage where it needed to be. No big deal, but I worried a little that maybe that was just too easy, and the problem was bigger. Thankfully there are guys like us that subscribe to this message board and assist folks, or I probably would’ve pulled the rest of my hair out.
Anyway, thanks for your reply, nice to see folks are always willing to help out...you never know when a problem will hit you, and after all of that work, sometimes it’s tough to see easy fixes right in front of you!


Anyway, thanks for your reply, nice to see folks are always willing to help out...you never know when a problem will hit you, and after all of that work, sometimes it’s tough to see easy fixes right in front of you!

- neikeel
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Re: NEED HELP! 50w kit
If you are swapping lots of tubes a different range pot is useful 0-100k for example.
Regarding the vol 1 bypass cap if you look at the interaction with the pot values a 500pF is very spiky. I tend to use a 100pF for amps that get used at lower volumes. The original lead amps all run 5,000pF, any thing else is a mod, and the plexis are usually very smooth in comparison with the metal panel amps.
What cap are you running on V2a and what NFB resistor/tap combo?
What sort of tones are you after?
Regarding the vol 1 bypass cap if you look at the interaction with the pot values a 500pF is very spiky. I tend to use a 100pF for amps that get used at lower volumes. The original lead amps all run 5,000pF, any thing else is a mod, and the plexis are usually very smooth in comparison with the metal panel amps.
What cap are you running on V2a and what NFB resistor/tap combo?
What sort of tones are you after?
Neil
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Re: NEED HELP! 50w kit
Honestly I removed the bright cap completely, sounded much better! V2A cathode resistor/ cap combo are an 820/.68uf. NFB is a 100, attached to the output jack positive terminal. Was looking to heat up the power tubes without teeth grinding highs, so removing the bright cap got me there. Could’ve used a 100, but the lowest I had was a 250, and I figured that wouldn’t be enough. Turned out great!