Sorry but that schematic is wrong.
Transformer tap #6 will be shorted to ground on negative semicycles.
And tap #8 is shorted to ground all the time through the bottom 470uF capacitor.
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Wait just a second.
The answer to that question is yes. But that's not what you have. You don't have "one secondary" and the "other secondary". You have one secondary with multiple taps. That's a different kettle of fish. You need to make sure it's properly designed and wired. As said, you have a short in there.
Make sure it's all correct and run a sim if in doubt. Otherwise things can go boom ouch.
The answer to that question is yes. But that's not what you have. You don't have "one secondary" and the "other secondary". You have one secondary with multiple taps. That's a different kettle of fish. You need to make sure it's properly designed and wired. As said, you have a short in there.
Make sure it's all correct and run a sim if in doubt. Otherwise things can go boom ouch.
This is a PP pentode connected 807 5-20 inspired amplifier I am building from my own schematic. I was hoping to get 300V for a screen supply off of the other secondary tap. I was pretty certain it was incorrect which is why I asked for help.
You could try hooking those taps up to a couple of UF4007 diodes with a small choke input filter to crank the voltage down. Screen current is pretty minimal, so this may indeed be a reasonable option.
you can learn it the hard way, or you can use caps to isolate your voltage doublers input voltages...
why not just use a simple voltage double and use the center voltage to supply the screens? i do that all the time.....i even use chokes at the center voltage tap where the two caps meet....
i try to avoid complicated situations as much as i can...
i try to avoid complicated situations as much as i can...
The "half-wave" doubler circuit could be used, or two, one from each tap. The "full wave" doubler shown can't share a common with anything else on the transformer.
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If it is just for the screen supply why don't you take an OD3 or other VR tube and feed that of your main B+? It'll be extremely stable
With the current (external) power supply, I am using two OD3 off of the B+ and that works fine. I am building a new power supply for the amp with greater current capability and the second set of taps off the secondary was tempting me to use them.
The half wave doubler appears to be a practical approach.
The half wave doubler appears to be a practical approach.