I have a B-Line that has been running fine for a few months now after a general service (replaced all the caps, checked resistors, cleaned the band switches, etc.) All of a sudden last night I noticed that I get no indication of idle current (bias setting) on the T-4XB. I can still Tune in Lower (x) mode and get full power output. However if I just key the PTT, or put the transmitter in Tune in upper sideband mode (per the manual) I see a reading of zero on the meter. The meter resistor was replaced with that initial service. Prior to last night I would always see the requisite current at idle on that meter. Now the meter does not move at all until I modulate. I tried adjusting the bias pot on the AC-4 of course. This made no difference. I can measure the bias voltage (-40 thru -60) all the way at pin 2 of the finals. So I know I am getting the bias voltage from the AC-4 and it is making it to the grids. Screen voltage is ~255V at each final tube. The resistances around the finals seem to match the chart in the manual, as do the voltages. (Within some variance for old equipment and modern line voltages.) It does not matter if I use the VFO in the Transmitter or Receiver, or the xtal mode in the receiver. Any clues would be appreciated. Thanks in advance. Edit: I do see that I am only getting an indication of about ~190mA on the meter when tuning full power. So maybe something is up with the meter circuit, but I would still think it would move a little bit at idle. Right now I don't see any movement. Also, the current level has been about that (with line voltage variance) for the past few months.