Pins 1 and 6 both measure about 4vdc. Over 200vdc dumping across plate load resistors.
1-Changed plate load resistors,no change
2-Checked filament voltage between 4-9, 5-9. Normal
3-Checked continuity from tube socket to corresponding parts on pcb. All good.
4-Cathode resistors check out and are grounded.
5-Reflowed solder on pcb tube pins.
6-Replaced V1 preamp tube.
Thanks
Extremely low plate voltage on v1 Blues Junior green board
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Stevem
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Re: Extremely low plate voltage on v1 Blues Junior green board
Yank out the power tubes, do you than have over 330 volts on there pin 7?
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Re: Extremely low plate voltage on v1 Blues Junior green board
The actual problem as it turns out, after pulling main and tube pcb, there was some crud residue at the solder joints at each end of the ribbon cable causing a short between grid and plate. Cleaned crud. Amp works.
Thank you for responding
Thank you for responding