[Amps] A thought about regulating fil voltage...

[Roy Koeppe]

the easy way??

It came to mind that two series strings of hefty, stud-mounted, low
voltage diodes could be installed back to back polarity across the
filament, effectively acting as a shunt regulator (ahead of the filament
choke in case of GG service). Without the diodes in the circuit, voltage
would preliminarily adjusted to slightly higher than normal. Then the
proper shunt diodes would be installed to clamp it down to the correct
value. Ideally not much current would flow into the diodes, maybe on
order of a few amps. The diodes would be RF bypassed.

Now, when you key up the idling current, and more so the full RF drive,
filament voltage could thus be stabilized.


I have not tried it--I just saw it in a 'night vision'.

Thoughts please.

73,     Roy          K6XK/0