Ceriatone King Kong User Manual page 13

In this diagram, we have color coded five features for simplicity
1) Green arrows = red bias probe jack, V6, V7, V8, V9 (from left to right, respectively)
2) Yellow arrow =black bias probe jack, ground ("COM")
3) Blue arrow = bias adjustment potentiometer shaft,
To measure your power tube bias, carefully follow these steps with the amplifier in OPERATE and connected to a speaker
load (not doing so may damage your amplifier!):
1) Turn on a digital multimeter (DMM), and set it to read millivolts (mV) in the 100mV range (this will vary from DMM to
DMM)
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