I have a fender roc pro 1000 head that powers down on me.

[blttlive]

I have a fender roc pro 1000 head . powers on works for 20 minutes then powers down .if i wait ten minutes and it will power back on it keeps doing this . could it be the tube ?
Anybody have any ideas on what it could be

[Enzo]

OK, so you mean it literally shuts off the power - no lights noi activity - as opposed to just losing sound?   In that case, no, I don't think it is the tube.

REach up under the chassis and feel it when it shuts down, is the chassis HOT?  A thermal sensor turns off the mains power to the amp when it gets too hot.   That allows the amp to cool, and after a few minutes it cools enough to come back on.   So we need to know if it is heating.

[blttlive]

OK, so you mean it literally shuts off the power - no lights noi activity - as opposed to just losing sound?   In that case, no, I don't think it is the tube.

REach up under the chassis and feel it when it shuts down, is the chassis HOT?  A thermal sensor turns off the mains power to the amp when it gets too hot.   That allows the amp to cool, and after a few minutes it cools enough to come back on.   So we need to know if it is heating.

yeah it shuts down no lights or activity. the chassis was pretty warm .

[Enzo]

Then that is where it starts.  We verify the thermal sensors are turning off the power.  And if so, why is the amp getting hot.

[blttlive]

Then that is where it starts.  We verify the thermal sensors are turning off the power.  And if so, why is the amp getting hot.

cant figure it out yet.

[DrGonz78]

Take the chassis out of the enclosure and run it for at least ten minutes no speaker... Does the area of the chassis that is just below R37, R38 & R39 feel really hot? Try it for ten minutes with speaker connected and playing guitar. Does that same area feel really hot now?

I have the Roc Pro 700 which is a similar model but in combo amp form. I notice that area getting really hot on my amp once. I then sat there for a while trying to see if any chips were getting hot but it was not the output transistors connected to the heat sink getting hot. Instead I am pretty sure those wire wound resistors were generating a lot of heat. Test the voltage as 40vDC at R38 to ground and see what happens to the voltage after 10-20 minutes. Maybe something is heating up in this area. Very vague I know...sorry. That area of the amp gets really hot as I recall so that is where I would spend some time looking.