Power problem with 6506!! help!

[MEGA DAVE]

Got a friend on tour with a 6505 and having a problem where when he turns on the power it powers up fine and the tubes light up but when he flips the standby switch on the green light doesn't light up and gets no sound. any advice or ideas what it might be?

 

[BLUElightCory]

Check the fuses - There are (I think) two fuses on the back and one internal fuse. Two of the fuses can be blown and the amp will still power up.

 

[Sweetnothing]

Mine blew last week and did the same thing, fuses were replaced, the tech said something about a blown up component inside

I have this bad luck regarding 6505/5150's, the 3 I've had over the years ended up breaking the same way
It has been like this each time:
noise buildup-->blown fuse--->change fuse--->big spark on 4th power tube--->completely blown up

 

[Wolfeman]

It sounds like the fuse for the heaters is blown. Just don't replace the fuse, you have to find which tube is causing the issue and replace that too.