Quote:
Originally Posted by DaveWM
the HV adj should not "seem to work" it should work, in a very linear fashion.
Disconnect the pot from the circuit and confirm (preferably with an analog ohm meter) that it is working as it should (500k to near 0 resistance as you adjust).
Confirm the voltage readings at the shunt tube grid and cathode, make sure the grid varies with the pot.
Confirm the total bias of the shunt tube is within specs of the sams.
At some point I recall you saying the HV would go to 30kv with out the CRT anode attached.
If now you are saying the max is 19kv without the CRT attached then only 3 things can be wrong.
Remember you are working with high voltages all over the place (400v around the cathode and grid of the shunt, 30kv at the anode) so be careful.
1) bad shunt tube
2) bad shunt tube bias
3)no loner getting 30kv with shunt tube disconnected.
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this set is nuts, lol, lol, the 30kv was with the shunt tube cap off. i have tried 4 shunt tubes all had the same result , no change. as for the voltages at the shunt tube they were where they should be. and 19kv was with the anode wire off the crt. as well as the currant too was ok. i had unsoldered the pot and checked the ohms and again was good.