Originally Posted by wagtailblue
I've just repaired a faulty Valve Senior and the output stage cathode resistor was far too small in my opinion. Meaning that the 6V6GTs in the output stage were running VERY hot indeed - one had died as a result. I've swapped the "stock" 250R 10W resistor with a 680R which placed the output tubes in their safe operating region. I changed the undersized bypass cap to a 47uF 100V (the old cap had exploded!).
I also added additional 470k grid resistors to the output stage to maintain grid bias in the event of the cheap-quality master volume pot developing an open circuit. Also, added an inline internal HT fuse.
A cheaply made product. It seems you get what you pay for!
Well, Ive had a Valve Senior combo that I had purchased from MF on a whim. It was a used special for like 200 bucks.
I turned it on, played some tunes, turned it off for a couple of months. and until recently started playing it again.
Well , after about 5 or 6 minutes, the thing just dies. Consistently at around the same time.
I cant return it to MF,because Ive had it for too long. It was my fault for not playing the thing for about an hour after i got it. :(
Anyway, wagtailblue, is this what was happening with your VS?
The tubes are fine. I put them in a THD Unilvalve, and have tried other tubes as well, but the unit just dies after about 5 minutes.
Any suggestions would be appreciated. thanks!