i have a pignose g40v i got an and am trying to breath live into it.
i'm using it a my first project to try and understand more about tube amps. the power transformer doesn't seem to work and i'm wondering if anyone knows a way i could verify that it is bad. visual inspection shows no sign of blowing up. i have made a voltage limiter and get nothing but have power at the two line voltage taps at the transformer. is there a test i can do to determine if it is toast? if it is bad does anyone know a good source for a replacement??
thanks
i'm using it a my first project to try and understand more about tube amps. the power transformer doesn't seem to work and i'm wondering if anyone knows a way i could verify that it is bad. visual inspection shows no sign of blowing up. i have made a voltage limiter and get nothing but have power at the two line voltage taps at the transformer. is there a test i can do to determine if it is toast? if it is bad does anyone know a good source for a replacement??
thanks
Torched TX.
Dave, if you have the transformer out ..separate the primary windings from the secondary windings...as you have pulled it out you should know this as you know what wire went where..right?
Do a simple resistance check on the primaries & secondaries.
If it is still installed, do a secondary winding AC voltage output.....some high values for the mains..some 300 or so volts & some low values...6.3 volts for the heaters.
Please be careful measuring these voltages as they are high and can readily kill you...or at least throw you across the room if your not CAREFULL!
____________________________________Rick.........
Dave, if you have the transformer out ..separate the primary windings from the secondary windings...as you have pulled it out you should know this as you know what wire went where..right?
Do a simple resistance check on the primaries & secondaries.
If it is still installed, do a secondary winding AC voltage output.....some high values for the mains..some 300 or so volts & some low values...6.3 volts for the heaters.
Please be careful measuring these voltages as they are high and can readily kill you...or at least throw you across the room if your not CAREFULL!
____________________________________Rick.........
the trans is still installed and has two wires which go to the primary side and two pairs of wires on the secondary side, one pair of which goes to a PCB and what I assume is a solid state rectifier, the other pair go to the first power tube. So what I should do is test to see if I have any power at these leads? My wiring schematic shows 324 vac going to the rectifier and 7.2 volts to the fillaments.
thanks
thanks
Troubleshooting...
Dave:
OK, yeah you got it right...It would be a good idea to power down the filament voltage just for testing purposes as you don't want to run your tubes with zero high voltage but filaments up and running.
If at all practical, remove the "other" wires at the PCB to test the other HV lines going to the tubes
Given the realative 'openess' of tube chassis' you should be able to "clip" these wires to keep the filaments "unpowered".
So ...as you have these secondary windings "exposed" & ready to test ...be very careful.....
Check your multimeter for its' capability of registering these high voltages.
______________________________________Rick.........
P.S. I lived in the Portland metro area (Hillsboro last) for many many years before coming down here......It's cold here now!
Dave:
OK, yeah you got it right...It would be a good idea to power down the filament voltage just for testing purposes as you don't want to run your tubes with zero high voltage but filaments up and running.
If at all practical, remove the "other" wires at the PCB to test the other HV lines going to the tubes
Given the realative 'openess' of tube chassis' you should be able to "clip" these wires to keep the filaments "unpowered".
So ...as you have these secondary windings "exposed" & ready to test ...be very careful.....
Check your multimeter for its' capability of registering these high voltages.
______________________________________Rick.........
P.S. I lived in the Portland metro area (Hillsboro last) for many many years before coming down here......It's cold here now!
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