Hi guys,
Here is a pretty nice PS from a vintage all tube Novacord synthesizer.
As you can see there is a nice noise cancelling circuitry instead of the usual big choke/caps design.
I've read that the tone part of this equipment was generating a lot of harmonic so that PS was designed to cancel those harmonics. True, false? I don't know.
One thing I do not understand is the 6K6 bias (both).
To me it seems like those triodes have the grid elevated compared to the cathode, therefore a positive bias ? How could this work?
Thanks.
Here is a pretty nice PS from a vintage all tube Novacord synthesizer.
As you can see there is a nice noise cancelling circuitry instead of the usual big choke/caps design.
I've read that the tone part of this equipment was generating a lot of harmonic so that PS was designed to cancel those harmonics. True, false? I don't know.
One thing I do not understand is the 6K6 bias (both).
To me it seems like those triodes have the grid elevated compared to the cathode, therefore a positive bias ? How could this work?
Thanks.
Attachments
It is a typical shunt regulator supply.
With the screen and control grid tied together, the 6k6 will need some positive grid voltage to conduct.
Think of the 6j5 as a cathode follower driving the 6k6 grids positive. The first 6k6 is a shunt regulator and the second 6k6 is to hold the 70 volt output right.
With the screen and control grid tied together, the 6k6 will need some positive grid voltage to conduct.
Think of the 6j5 as a cathode follower driving the 6k6 grids positive. The first 6k6 is a shunt regulator and the second 6k6 is to hold the 70 volt output right.