Orange AD30TC Head .....low output?

[boxofknobs]

Hey all,
Having some issues with an AD30TC, the head not the combo. I tested the following test points and replaced 2 grid resistors (1.5k off of pin2 of EL84's were black and crispy). Still getting low voltage on the test points but the other parts look and test out fine. Any suggestions?

Its just a hair under bias also. Should be getting 11DC on TP 9 and 10....Getting more like 9v on TP 10 but TP 9 is fine.



Not sure what to do now.....Any ideas?



300DC @ TP5, Should be 335+/- 10v

289DC @ TP6, Should be 320

222DC @ TP7, Should be 245

189DC @ TP8, Should be 210

[mozwell]

i think this is the sch.....

is there an actual problem with the amp, or did you measure the DC voltages & saw they were a little low ?
is the PT set to 240V position & you have 220VAC supply ?

[boxofknobs]

i think this is the sch.....

is there an actual problem with the amp, or did you measure the DC voltages & saw they were a little low ?
is the PT set to 240V position & you have 220VAC supply ?

The amp is running at about half of the normal volume. I have two of them, the head version is what I am working on. After replacing the resistors, the volume went up a bit (maybe 20%).

PT is dead stock. It is supplying correct voltages...


Also, that Sch is for the AD30R version.....has the same power section but some of the resistor and cap numbers aren't correct to the TC.