24-07-2017, 09:59 PM
Not impossible. Output phase is the anode load. If signal voltage on grid is postive, anode current increases. Multiply that current by the anode load resistor and the sun is higher. Therefore the anode voltage falls and is out of phase with the grid cathode voltage. Yet the anode load is in phase. If the anode load was a bulb it would glow, consume watts and detract from the valve. If HT is 300 volts and fixed anode cathode voltage is 100 volts, you get 200 volts across the load resistor. Yet a varied signal on the grid can swing the current value and vary the load drop.
