[Kenwood] ts-820s voltages

[Dr. Gerald N. Johnson, electrical engineer]

PA control grid voltage should always be negative. -100 volts is cut off
during receive to keep the tubes from wasting energy and creating noise
in the receiver. -47 or -60 volts sounds about right for transmit but
should be set for the rated idling current with no drive to keep the
tubes in their most linear operating region. Normally a pair of 6146
needs to idle at 40 to 50 ma.

In general you can think of vacuum tubes as being depletion mode FETs,
they always require a negative bias on the control grid to keep them
from drawing saturation current.

The driver plate voltage ought to be closer to 310 volts than 64 volts.
The RF will confuse many meters.

73, Jerry, K0CQ

-- 
Entire content copyright Dr. Gerald N. Johnson, electrical engineer.
Reproduction by permission only.