C+ voltages

[Shep]

This is to high.. plate 503V, screen grid 499, grid 1 -49.3 outter pair,-61.2 inner pair..heater 3.32 volts AC

Just thought i would share...

I am going to call mike b when i can work out the time zone difference...

 

[stokes]

Just a guess,but it is possible the tubes you have in there are biased too cold.If you bias a little hotter it will likely bring the plate and screen volts down where they belong.I assume the heater voltage you posted is one side of the heater measured to ground.If you check the ac voltage connecting your meter to pin 2 and 7 of your power tube you will get 6.3 or better.

 

[Boogiebabies]

This is to high.. plate 503V, screen grid 499, grid 1 -49.3 outter pair,-61.2 inner pair..heater 3.32 volts AC

Just thought i would share...

I am going to call mike b when i can work out the time zone difference...

All my Simuls run -46-47 on the outer sockets and -56-57 on the inner. The plate voltage is exactly 483 on all three. Your pin 5 readings are more similar to the 105 readings than the X101. The Export was biased hotter because the plate voltage is lower, thus needing a bias adjustment. The lower the plate voltage, the more negative readings you will see when adjusted to Mesa spec or with a bias pot. With 503 plate volts your probably lucky they did not mess with the bias or it would be running too hot at the Mesa spec for the Export. Like Stokes said, if your tubes are biasing really cold, they are not drawing voltage from the tubes due to low natural plate current.

Don't forget to connect pins 1 and 8 on the outer sockets. Your EL34's will be much happier.

 

[Shep]

Hey BB i am going to put the 105 back in and run it at 110V with a step down transformer.. can you tell me What the orignal 105's lead colour's do What?

i checked the plates of the 12ax7's are it's 400V ..Way to high.. The heater's are 6.7 volts and the plates of the outter pair is red plating..

The 105 should Fix Everything and maybe even sound Better..