Hi, just got a second hand Dynaco's mk3. Bought it as a modded ones.
Upon inspection, I found that the ultralinear taps unused and instead to have a separated transformer feeding a 240Vdc to the pins 4 of the 6550 output tubes.
I have to say that this amp do have a solid state rectifiers and extra 1000uF at 800Vdc caps of power supply filtration.
B+ is at 500Volts.
It use the standard 6AN8 input/driver boards.
I know in certain Heathkit and Fisher amps the screen supplies are derivative from B+ with RC filters, but why not use ultralinear taps on original output transformers??
I know that the ultralinear taps are part of the design of Dynaco to minimize THD. Globalized with NFB.
Just a curiosity.
I know in big FM transmitter plate B+ supply do have a separated screen supply, make sense in non output transformer design as FM is RF couple to the antennas.

Upon inspection, I found that the ultralinear taps unused and instead to have a separated transformer feeding a 240Vdc to the pins 4 of the 6550 output tubes.
I have to say that this amp do have a solid state rectifiers and extra 1000uF at 800Vdc caps of power supply filtration.
B+ is at 500Volts.
It use the standard 6AN8 input/driver boards.
I know in certain Heathkit and Fisher amps the screen supplies are derivative from B+ with RC filters, but why not use ultralinear taps on original output transformers??
I know that the ultralinear taps are part of the design of Dynaco to minimize THD. Globalized with NFB.
Just a curiosity.
I know in big FM transmitter plate B+ supply do have a separated screen supply, make sense in non output transformer design as FM is RF couple to the antennas.