Quote:
Originally Posted by DaveWM
lets break it down
all the following with CRT anode off to take the CRT out of it.
shunt cap off
30kv at anode lead
shunt cap on
19kv to 22kv
HV setting to max
so the shunt is drawing current with pot a the max HV setting
two things can cause it to draw excessive current
1)bad shunt tube (gassy/grid emissions), replace with a KNOWN working one.
2)incorrect bias (voltage divider resistors/pot)
leakying cathode/grid cap on shunt tube (upsetting the bias as well).
It has to be one of the above.
Did you alter any wiring around the shunt? does the cathode resistance to ground change the the HV pot?
do you have resistance checks for the tube pins on the shunt.
did you REPLACE the grid to cathode cap on the shunt? if so did you make sure the replacement cap was good?
|
ok your right so far but the reg tube i had tried working ones, known working i didnt alter anything at all in the set and the cap i think you are talking about cathode cap i believe it was a disc cap and i got one from moyers but it looked to small even though it was marked as the right one i still had no luck so i found on ebay nos caps and put that one in, was like the original i had changed in the first place. i have the ma specs in earlier posts on the regulator and they appeared ok to a member, it my have been you. you mention voltage divider resistors, where exactly are they? if its the high wattage ones around the hv pot i already did check them. i dont remember if i did resistance checks on the hv reg tube but i do believe i did because i do remember doing all of the others taking awhile to do so.
so i dont think i would have left that one out.