5150 mkII won't come out of standby

[Sdzfsn]

Hi My 5150II is suddenly acting up. I can power it on but thats as far as I can get, it wont come out of standby. I think the reason something has happened is due to the fact that when I gig/travel the amp is exposed to road vibrations (I'm saving for a flightcase).

I had a look inside and all the fuses tested fine, I replaced the power tubes and still nothing, and the preamp tubes are only about a year old.
Can anybody give me some advice on other parts of the amp to check? I have to fix it in the next ten days and I am very new to this, all the repair shops in my area are too busy to have it sorted by then.

Any help would be great thanks!

[Amp Kat]

Hi My 5150II is suddenly acting up. I can power it on but thats as far as I can get, it wont come out of standby. I think the reason something has happened is due to the fact that when I gig/travel the amp is exposed to road vibrations (I'm saving for a flightcase).

I had a look inside and all the fuses tested fine, I replaced the power tubes and still nothing, and the preamp tubes are only about a year old.
Can anybody give me some advice on other parts of the amp to check? I have to fix it in the next ten days and I am very new to this, all the repair shops in my area are too busy to have it sorted by then.

Any help would be great thanks!

Put a cord from send to return and see if it will come back. No noise at all ? nothing ?

If that doesn't work you may need to pull a tube and do some voltage checks so do you have a multimeter ?

[Enzo]

I am going to go ahead and suspect your 400 ohm resistor on the power tube board is open. But KB is right, pull a power tube and look for voltages at the pins Pins 3 and 4 need about 480-500vDC and pin 5 needs about -55vDC.