Laney TT50H No Outout

[g1]

The boost switch doesn't matter right now. You have signal at line out so that is all the way to the PI grid (V6).
What areDC voltages at pins 1 and 6 of V6 ?
Power tube voltages pins 3,4,5, and 8 ?

[ca7922303]

The boost switch doesn't matter right now. You have signal at line out so that is all the way to the PI grid (V6).
What areDC voltages at pins 1 and 6 of V6 ?
Power tube voltages pins 3,4,5, and 8 ?

V6-1(250vdc)6-(234vdc)
V7/V8--3(445vdc)4(440vdc)5(-39vdc)8(0.5mv)

[g1]

Speaker and speaker cable are good? Unplug the speaker cable from the head and measure resistance right at the plug.

[ca7922303]

Speaker and speaker cable are good? Unplug the speaker cable from the head and measure resistance right at the plug.

Speaker and cable are good. Get a audio signal when running thru line out using several different cables.

[g1]

Have you tried plugging the guitar into the FX return jack?

[ca7922303]

Have you tried plugging the guitar into the FX return jack?

Yes, went thru return fx and record out. No output.

[ca7922303]

Have you tried plugging the guitar into the FX return jack?

I've got a signal generator. Tracing signal at this point? What would be good settings on generator to use?

[g1]

Do you have the FX mix set to 10 by any chance? If so, with nothing plugged in to the loop, you will not hear anything from the speaker.

If not, try putting a 100 milli-volt RMS signal into the FX return jack. See what AC voltage you then measure at pin5 of the power tubes.
FX mix will need to be turned up to 10.

[ca7922303]

Do you have the FX mix set to 10 by any chance? If so, with nothing plugged in to the loop, you will not hear anything from the speaker.

If not, try putting a 100 milli-volt RMS signal into the FX return jack. See what AC voltage you then measure at pin5 of the power tubes.
FX mix will need to be turned up to 10.

Not sure what to set signal generator at and am I plugging signal into instrument jack or return fx jack? Thanks. Signal generator is set @ MF=0000400.00Hz and AMPL=00.30V SINE

[Enzo]

try putting a 100 milli-volt RMS signal into the FX return jack

He told you how much and where to plug it. 400Hz? That is fine. So would be 1000Hz or 200Hz. Keep your eye on the prize. We are fighting and amp that makes ZERO sound out the speaker, right? SO it doesn't matter at this point if your test signal is loud or soft, high or low in tone, even clean or distorted. All we want at this moment is to find why the amp doesn't make sound. We can worry later what the sound sounds like.

In fact, sometimes in my shop, when I just want a go/no-go test, I just plug a cord into the input jack and at the free end of the cord, I just touch the tip with my finger. Normally that makes a loud HUM. If I get the HUM, then the amp works and I can move on to the quality of sound. But if my touch doesn't make sound, then I have to find out why.

Test tones are hard to listen to for very long, so unless I am looking for some exacting tests, I just plug a CD player into the amp and listen to that.

[ca7922303]

Do you have the FX mix set to 10 by any chance? If so, with nothing plugged in to the loop, you will not hear anything from the speaker.

If not, try putting a 100 milli-volt RMS signal into the FX return jack. See what AC voltage you then measure at pin5 of the power tubes.
FX mix will need to be turned up to 10.

OK, had to resolder p20 on main power board, now with signal thru instrument jack, channel one is working, channel two has a loud hum only and channel three has no output.

[ca7922303]

OK, had to resolder p20 on main power board, now with signal thru instrument jack, channel one is working, channel two has a loud hum only and channel three has no output.

Got 0.0vac at pin #5 of power tubes

[g1]

Got 0.0vac at pin #5 of power tubes

Is channel 1 working normally and you can get proper volume out of it? If so, we don't need to look at power tube pin5's any more.

[ca7922303]

[X=g1;n951636]

Is channel 1 working normally and you can get proper volume out of it? If so, we don't need to look at power tube pin5's any more.[/QUOTE]

Channel one appears to be working normally.

[g1]

Has the boost switch been installed or not?