Palstar COMMANDER VHF-144 Owner's Manual - Introduction
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INTRODUCTION
The Commander VHF-144 is a grounded grid AB2 linear power amplifier that oper-
ates on the Amateur 2 meter band (144 to 148 MHz).
A single CPI/Eimac 3CPX800A7 pulse-rated external anode triode with forced air
cooling and modern stripline circuitry ensures efficient and conservative operation.
The 6:1 ratio vernier reduction drives on all tuning controls allow smooth and easy
tune up, while the front panel input tuning control allows a higher input circuit "Q" for
excellent linearity which presents a low input VSWR to the exciter across the entire
2 meter band.
An automatic delay circuit, for proper cathode conditioning before RF drive is applied,
which extends tube life. This is preformed by a microprocessor, which also controls a
step/start dual relay system for a safe and effective control AC input startup.
The Commander VHF-144 features a full compliment of control and metering func-
tions for easy on-air operation. By using 2 cross-needle metering, it allows viewing of all
functions simultaneously.
This processor also features a gird-trip at 70ma of grid current. When activated by
overdriving the amplifier, the green LED will flash at a high rate.
Reset is provided by switching the operate/standby switch from operate to standby and
back again.
A dual primary power transformer allows 117VAC, 200VAC or 234VAC operation.