Ceriatone Son of Yeti User Manual page 11

20w lunchbox mini guitar amplifier

To measure your power tube bias, carefully follow these steps with the amplifier in OPERATE, MASTER at minimum, 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)

2) Plug a black probe into the color-coded jack on your DMM, and do the same for a red probe

3) Plug the black probe tip into the COM multimeter jack on the rear of the Son of Yeti.

4) Plug the red probe tip into the top BIAS multimeter jack on the rear of the Son of Yeti. This measures bias for the 6V6

closest to V3. Right down the value your DMM reads. You might expect a value between 23mV and 25mV.

5) Repeat for the other power tube position by plugging your red probe into the bottom BIAS multimeter jack.

Okay, now I've measured my bias. Now what?

To calculate bias, there are two pieces of information you need to know: your amplifier's power tube plate voltage, and the

published value for maximum plate dissipation for the power tubes used in your amplifier. To save you some time and energy,

here are those two values:

- Approximate plate voltage for Son of Yeti amplifiers =

- Maximum plate dissipation for 6V6s

...and now some math. The formula for calculating bias is as follows:

��

× �� × 1000 = �� (��)

380-390VDC

14W

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