Ampeg BA115HP Output and crackling/static

[ca7922303]

Connected drain/source of Q9, now no output. Replace Q9?

[g1]

Drain to source should be pins 1 and 2, see attached datasheet. Double check those are the pins you connected. There were some datasheets with an error which showed D and S as pins 2 and 3 which is not correct.
It's not possible that connecting D and S of Q9 would kill the signal. At least not if the schematic is correct.

[ca7922303]

Drain to source should be pins 1 and 2, see attached datasheet. Double check those are the pins you connected. There were some datasheets with an error which showed D and S as pins 2 and 3 which is not correct.
It's not possible that connecting D and S of Q9 would kill the signal. At least not if the schematic is correct.

It's printed on the board

[ca7922303]

Drain to source should be pins 1 and 2, see attached datasheet. Double check those are the pins you connected. There were some datasheets with an error which showed D and S as pins 2 and 3 which is not correct.
It's not possible that connecting D and S of Q9 would kill the signal. At least not if the schematic is correct.

Board is printed right according to data sheet. I must have bumped gate.

[ca7922303]

J111(Q9) takes about a month to get. J112 a couple of days. Seems close from data sheet. Think it will work in place of J111?

[g1]

Was it passing signal after you replaced C11? It is best not to tack on components to the old leads like that. Sometimes it will loosen the solder on the bottom side of board and you get a bad connection.
If you get no sound now when shorting D to S of Q9, the problem is elsewhere. It should work with Q9 removed if D to S solder pads are connected. Q9 serves as a power amp mute when headphone jack is in use.

[ca7922303]

Was it passing signal after you replaced C11? It is best not to tack on components to the old leads like that. Sometimes it will loosen the solder on the bottom side of board and you get a bad connection.
If you get no sound now when shorting D to S of Q9, the problem is elsewhere. It should work with Q9 removed if D to S solder pads are connected. Q9 serves as a power amp mute when headphone jack is in use.

There was signal after tacking on C11 on top of board. Did that temporarily while testing. Had already removed and reinstalled board once. Have no signal at all now, with or without source/drain jumped.. Should I remove Q9 to see if signal comes back?

[g1]

It won't pass signal with Q9 removed as there will be no signal path from R25 to U5. Do you still have signal at headphone out?

[ca7922303]

It won't pass signal with Q9 removed as there will be no signal path from R25 to U5. Do you still have signal at headphone out?

Headphone out works normally if no speaker is connected to speaker out jack. If speaker is connected and headphone, there is a signal at speaker out, but alot of background noise, but not the static described originally. If speaker is connected and no headphone, there is no signal thru speaker

[g1]

Check resistance from Q9 gate to ground, with and without headphones plugged in.

[ca7922303]

Check resistance from Q9 gate to ground, with and without headphones plugged in.

Q9 gate to ground w/o headphones(0.8 ohms)
Q9 gate to ground with headphones(23ohms)

[g1]

Remove Q9, jumper D to S traces. Check sound at speaker and at headphones.

[x-pro]

Signal is my phone playing an audio file.

I don't think this is correct if the phone is connected to the J25 input.
Not all headphone outputs have isolation capacitors at the output. And there are none at all after J25 and the adder. This can change the mode of operation of U3:A. And when you change the level with LEVEL control, it can cause rustling and crackling.

[g1]

Not all headphone outputs have isolation capacitors at the output. And there are none at all after J25 and the adder. This can change the mode of operation of U3:A. And when you change the level with LEVEL control, it can cause rustling and crackling.

I guess you mean there may be DC at the headphone out jack of his phone?

[ca7922303]

Removed Q9, jumped drain to source,, headphones have output with or without speaker connected. Speaker has no output with or without headphones connected