Almarro has poping sound, please help


Recently, my Almarro 318B develop a loud "poop" sound. It is not very frequent. It is intermittent, usually have it after 15 mins or so after it is started. What should I do? I bought the unit used, and I have no history of the unit.
Should I take it to service, or should I try replacing the tube? Is there a way to find out if a tube gone bad? If I am to try replacing the tube, which one should I try first?
gte357s

Showing 2 responses by zmanastronomy

I've had the problem in the past and it was the output tubes. It's time to change the 6c33c's out.
I would highly recommend NOT buying your 6c33c's from ebay.
I have also gotten many dead tubes from there.
It's a cheap tube, so buy them tested.