13
Now that you know how to calculate bias, all you need to do is:
1)
Follow steps 1-5 on page 11
2)
Calculate what bias voltage reading you will set your tubes to (in this case, we will use 35mV)
3)
Insert your red probe in the probe jack of the power tube reading somewhere in the middle bias measurement of your
power tubes(variation in bias measurements from tube to tube is to be expected, so selecting one measuring in the
middle will approximate bias for all tubes)
4)
Turn the bias potentiometer shaft SLOWLY until your DMM reads 35mV
5)
Wait 1 minute
6)
Recheck all power tube bias measurements
7)
Readjust bias potentiometer shaft if necessary
A FEW COMMENTS ON BIASING
Due to the nature of vacuum tube amplification, there are inherent risks when biasing your amplifier. Extremely high-voltages
are present, and vacuum tubes reach high temperatures during use.
The risk of electrical shock and/or skin burns should ALWAYS be kept in mind. Therefore, bias at your own risk, and only while
paying attention and taking all precautionary measures.
Biasing should only be done on a clean workbench with no distractions. Do not wear loose clothing or any jewelry. Take your
time, and think carefully before each step.
Even though the bias test points and adjustment is external to reduce risk of electrical shock, all precautions must be taken
while biasing.
Again, bias at your own risk. Ceriatone Amplification is not responsible for any damages or injuries resulting from user biasing.
