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I'm having a little trouble with my Deluxe, it works but cuts out usually when played harder. I took some voltage readings, would anyone know where to look for the trouble.

VRM set to 400 volts at first filter cap, 2nd at 356 and 3rd at 255. C7 has been removed ( bypass cap on V2)

V1
Pin 1 97 (low)
Pin 3 2.8
Pin 6 98 (low)
Pin 8 2.3

V2
Pin 1 167
Pin 3 1.3
Pin 6 209 (high?)
Pin 8 45.5 (low)

V3
Pin 3 394
Pin 4 359
Pin 8 22.8

V4
Pin 3 394
Pin 4 359
Pin 8 22.8

The only other mods are the coupling caps changed to 0.022 uf.

Any insight would be appreciated.

Thanks, Dave.

Hi, I found a problem with the input jacks, it seems they weren't shorting to ground. I cleaned them up and the amp seems to be working again, no cutting out. Not sure how this problem affects the amp. I hope someone can help me with the odd voltage readings.

Thanks, Dave.

The voltages through a tube are the product of the resistors that feed them. So check both the plate and cathode resistors, and the solder connections.
Voltages can also very considerably with the tubes used.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Thanks, I checked the resistors and everything is OK, I will reflow some solder joints and see what happens. I seem to be having problems with the input jacks, is it common for the shorting contacts to act up? Should I change them out or is there a grease I can put on them?

Dave.

Not common. You can try aerosol contact cleaner, but I doubt it's the problem. More likely a solder joint .

Maybe see if this post helps too.

viewtopic.php?f=11&t=3522

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Thanks Stephen, I'll keep searching.

I took another look and the voltages seem passable. V1 plates are off, but workable. For fun, try another tube in v1 if you have one, or a 12AX7 and see if the voltages change much.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

The only tube I have that shows different plate voltages on V1 is an old Telefunken 12AX7, it shows 140 vdc on pin 1 and 146 vdc on pin 6. I tried a couple of 12AT7's but they were low and the original 12AY7 which was low and it has a hum in it. The Telefunken makes the amp quite a bit louder and it has a little more hiss, I guess because of the higher gain. I'm going to run it like this for while and see what happens. Thanks for your help.

Dave.