DPDT MBB toggle switches seem to be rare and MBB rotary switches are expensive. Would a DPST toggle switch be a closer implementation of your schematic? I guess I'm struggling with how to use a DPDT switch.
Yep, that would work too. Make sure it's a MBB or "Make before break" switch, sometimes called a "Shorting" switch. You don't want the cathode to go open between the two positions. It probably wouldn't kill anything, but it's best practice.
It's on the shelf for now. Trying to learn schematics beyond simple crossovers whilst building this amp is beyond me for now. I have a lot on my plate. My mental health needs some wins and this ain't it it with my skill level.
Yeah, that appears to be just a normal inline ma meter. You could add a simple bypass switch to the meter so it is bypassed when not being used to check the current. A DPDT could be used to bypass two meters.
It's not really needed. But one other option would be to put a switchable 100VDC meter directly across the cathode resistor and you would have a way to monitor the output tube current that way.
Could you elaborate a little. I have located a meter at youdaelectronics.com that appears to be made for measuring the amps at the cathode. Below is the schematic from their website. They describe it as "1PC SO52 DC 100MA panel meter with blue backlight for tube Amplifier speaker power supplier"
DPDT MBB toggle switches seem to be rare and MBB rotary switches are expensive. Would a DPST toggle switch be a closer implementation of your schematic? I guess I'm struggling with how to use a DPDT switch.
To clarify. A DPDT switch and two meters could be wired as shown below?
I would not want to leave a meter in the signal path, maybe if it has a bypass switch?
Unfortunately not. This meter was designed to work across the cathode resistor of a cathode biased tube amp.