The blue glow is not abnormal. Some power tubes flouresce like that, some don't.
How are you defining "low"? Less than you wanted, or hard to hear at all? Is the output low and distorted, or just low? If just low, it's probably something to do with the input wiring. If low and distorted, could be something more.
I see some unclipped component leads and improvised component fitting. Might check that nothing is shorted.
Win W5JAG
How are you defining "low"? Less than you wanted, or hard to hear at all? Is the output low and distorted, or just low? If just low, it's probably something to do with the input wiring. If low and distorted, could be something more.
I see some unclipped component leads and improvised component fitting. Might check that nothing is shorted.
Win W5JAG
The installation of the bias trim pots looks problematic to me.
They may or may not be your problem, regardless, a better way to mount those smaller than specified pots would be to use some scrap clipped off component leads, solder those scrap leads on both sides of the PCB to make sure there is continuity on both sides of the board, then form those leads over to the leads of the smaller component, solder the pot in, and clip off the excess ( if any ) lead length. Two uncut leads at R25 are available for this.
The smaller pots may or may not have the correct voltage / current capability.
Win W5JAG
They may or may not be your problem, regardless, a better way to mount those smaller than specified pots would be to use some scrap clipped off component leads, solder those scrap leads on both sides of the PCB to make sure there is continuity on both sides of the board, then form those leads over to the leads of the smaller component, solder the pot in, and clip off the excess ( if any ) lead length. Two uncut leads at R25 are available for this.
The smaller pots may or may not have the correct voltage / current capability.
Win W5JAG
I'm going by Georges Final Checkout and I run into a problem when I insert the input tubes(5842)and adjust the plate voltage to the input tubes. When I adjust the trim pot to get 175V (R20) I get smoke before I can get there. I'm currently getting 249 and 265 on the plates. Also to get my B+ to 300 and B- to -150 I have to set my voltage regulator to 80VAC. I have blown and replaced R28 and that is near where I get smoke from the bottom of the board.
Did you have "low" volume, but otherwise normal operation at first, but it is now smoking components, or has it been a component smoker since the get go?
Several things could cause the B+ and B- to read high. One cause could be that if you have a multi primary power transformer, it may be wired incorrectly. Or your voltages may be high because nothing is drawing current to pull it down. Your transformer could be wound wrong, but that is a long shot. An easy and safe way to tell if the power transformer is wired correctly is to disconnect either the 5 volt or 6.3 volt AC secondaries from the board, and measure them. They should be close to their nominal AC voltage. If they are off much, something is wrong.
In my experience, the only cause of excess plate voltage on the 5842's is a failed ( typically to a dead short ) 10M45 current regulator. I put over 500 volts on a 5842 when a 10M45 shorted, enough to make the tube brilliant orange, but it did not fail any of the other components. It was a pretty obvious event, so I caught it quick. The resistors should fail open. I would expect the 332 ohm resistor to be the one to fail under stress.
Did you install the 10M45's correctly? The (excessively) large heatsink makes it impossible to tell, and it may be shorting some stuff underneath and around it.
Win W5JAG
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