Vox AD15VT, Pwr amp works but now sound from input

[wblakesx]

When I pluga guitar in. If I put a line in and turn up the source volume I get some crackle with music but WAY below proper level.

The controls don't work with the exception of the amp modeler multi position switch.

I'm assuming the problem is in the digital section, if so is it worth fixing???

thanks in advance.-David

[wblakesx]

sorry, typo

should read:

Vox AD15VT, Pwr amp works but no sound from input

[Enzo]

How did you test the power amp?

Apply a steady test signal to the input. Is there signal at the top of the Master volume control? You won't see signal at its wiper, it is at virtual ground in the IC, but set the control midway and read at the top. IC1 is the input stages, is ther signal at its output pins?

Is there signal on the phones/line out jack? Remember it is a TRS jack, so shoving a plain old mono plug into it grounds off the ring.

[wblakesx]

thanks

I was injecting the audio into a line in the buss going to the power amp, got sound (seemed abouit 5 watts ). Then I tried going into IC 2 (I'm not up on pin # conventions nor surface mount so I'm a bit retarded here) this is when I got some sound, crackly and very faint, like afew/100s of a second on and then afew/10's off . IC 1 has a capacitor glued onto it so I have to heat it up to get it loose. I suppose I should get a magnifying glass too. I rarely work on amps, too many thumbs. But I do have some electronic repair background, just no digital experience.

I'll try to get back into the amp today or tomorrow (and find a better dmm)to check out your suggestions.- Thanks again- David