Jim Candela wrote:
Yea right! You would still run < 100 watts RF output
to keep the neighbors happy! Hmmm, power input 150
watts + plus 315 watts filament for 100 watts output.
Isn't that about 22% efficient? :-)
I'm running 4 250TH's in the rig now, at 1500v on the plates @ 100mA in
the final. That's 150w DC input, for 100w of carrier output.
I'm driving the final with a Viking II with an output of 50w, to get
125mA of grid drive, for a PAIR of 250TH's.
the modulator (a pair of 250TH's, as mentioned above) rests at 200mA at
1500v. That's 300w. Class A? At least AB1.
don't forget the speech-amp - a 50w Bogen PA, running 4 8417's in p-p
parellel
all that, yes, to do my part to keep the nieghbors happy.
Between 1 and 6am though, look out!
I shove the link in, for 300mA, the B+ goes up on the modulator to
2800v, the modulator bias is re-adjusted for 120mA (now in Class B), and
the knobs on the Speech-amp go another 'click' to the right (mic -and-
Master gain go from '3' to '4') and the final now produces 350w of
carrier output, with asymmetrical audio peaks of 5 and 6:1.
No problem!
:-)
--
73 = Best Regards,
-Geoff/W5OMR
