simonfck wrote:all parts oroginal
Live Voltage 122Vac
cannot adjust the bias voltage, bias voltage very high over 2.0vdc
rectifier tube is new. What should i check
across pin 2 and pin 7 6.9vac
half circle 459vdc
no symbol 493vdc
helf square 393vdc
If all parta are original and too much bias current ( you mention 2C and if it's original
1.56V is the "target) then i would suspect the selenium rectifier.
Replacing that with a single 1n4007 ( remove se-rect., mount a 2 point support and solder the
1n4007 and the connections there). Then at power up, remove rectifier tube and measure the
bias voltage , make shure its negative ( eyelet 6 or 21 on the board, same as pin 5 on the el-34)and about -30 to -40V .
If negative is correct, remove power and reinstall rectifier tube and power up, adjust bias
as per dynaco instructions.