Command Technologies COMMANDER VHF-2000 Manual page 7

INTRODUCTION
The Commander VHF-1200/2000 are Grounded Grid class
Ab2 Linear Power Amplifiers that operate on the Amateur 6
meter band.
Over-Drive and Over-Grid current protection is provided by
an Auto-Reset circuit the places the amplifier in Stand-By if
a preset limit is exceeded.
Genuine Eimac 3CPX800A7 External Anode Triode(s) with
forced air cooling and modern circuitry, insure efficient and
conservative operation.
Reduced ratio (6 to 1) vernier drives on all tuning controls
allow smooth and easy tune-up.
Rear panel input tuning control allows a higher input circuit
"Q" for excellent linearity and a low input VSWR to exciter all
across the 6 meter band.
An automatic delay circuit, for proper cathode conditioning
before RF drive can be applied, extends tube life. A 50 ohm
resister in the plate supply positive lead and a 200 ohm
resister in the negative lead protect the tube in the event of
an arc.
The Commander VHF-1200\2000 feature a full compliment
of control and metering functions for easy on the air
operation.
A Dual Primary Power Transformer allows 117 / 234 VAC
operation. Additional primary taps are provided for 200 VAC
operation. Operation of the VHF-2000 on 117 VAC is not
recommended.