bias unstable,low plate volts

bluze81 · Post by **bluze81** » Wed Jun 06, 2007 10:29 pm

Here I go again! new 50 build wont seem to hold bias setting, after shut down it takes a while,then power up and it seems to go higher from 37v to 45v without striking a note, and the plate volts has dropped from 435 to 415-420 and stays down, definitly lost tone ,its kinda flat,possibly this board I used has some bad components?or could bad contacts at pwer tube sockets cause this? any ideas come on wid it! thanks bluze

Flames1950 · Post by **Flames1950** » Wed Jun 06, 2007 11:32 pm

I'd start with the contacts at the sockets, and double-check the joint where the bias taps off the standby switch.

It all goes to pot after you decide to sell one, eh..........

bluze81 · Post by **bluze81** » Thu Jun 07, 2007 8:17 am

Thanks Andy, I will get into tonight and get it straight, it was sounding good so I know its in there, I had the same problem before on a 50w and George found some bad contacts at the tube sockets and it was a fix, bluze