mode switch schematic vs. wiring

[mete]

Do I understand this right ? In the schematic, SW is drawn to connect + terminal of Cbias to tube terminal 9 or Rtrickle, but in the actual wiring:

- Cbias + terminal is always connected to tube terminal 9
- SW connects Cbias - terminal to GND or Rtrickle which is then connected to GND

So effectively the wiring reverses the position of Cbias and Rtrickle; the path is tube terminal 9, then Cbias, then optionally Rtrickle, then GND.

 

[Paul Birkeland]

The schematic was drawn when we were thinking about using one of our 4P3T rotary switches to do a more complicated combination of switching, so that's what's been leftover in the schematic. The goal of the switch is to both switch out the cathode bypass cap but to also keep it charged when it's switched out, which is what the 100K Rtrickle is doing in the circuit.

 

[mete]

I understand, I was trying to mark the terminals on the schematic, so I realized the difference. You said "The goal of the switch is to both switch out the cathode bypass cap", but it is always connected as bypass cap no ? I understand it as switching Rtrickle in and out to decrease the effect of bypassing.

 

[Paul Birkeland]

The bypass cap is switched out when the trickle charging resistor is in series with it.