Antonio Vernucci wrote:
There are two other ways of handling the screen voltage in a modulated
stage. The screen can be feed by a regulated voltage supply and a
separate winding on the modulation transformer is used to modulate the
screen.

Unfortunately, as I had written, my transformer has a single secondary
winding.

A variation on this is to put an audio choke in series with the screen
supply and to optionally couple the screen to the hot side of the
plate modulator winding via a capacitor.

Yes, I had seen that method too on the ARRL Handbook (as well as in the
EIMAC booklet), but I was trying to avoid the bulk of an extra choke.

Nevertheless, browsing the Internet, I found a dealer who sells 20H 50mA
chokes of reasonable size at a reasonable price. So, I am getting more
and more convinced that that is the way to go.

Still, I would be interested to hear from someone who has actually tried
that method.

Thanks & 73.

Tony I0JX
You can also just ignore the issue and only apply modulation to the
plate of the pentode/beam power tube. In theory you won't reach 100%
modulation, however given that the screen input is a tiny fraction of
the plate input you'll probably achieve somewhere between 95-99%
modulation. You don't want to go over 100%, and unless you are using a
speech compressor you won't ever hit 100% modulation peaks when properly
set up anyway.