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2 meter, 200W driver amplifier.
Conduction-cooled 8072 tetrode.
Construction date: 1988.

amp photo

Brief description:
The 8072 is a conduction-cooled tetrode, identical to the well-known
8122 except that the 8072, with no air-cooling fins, clamps onto a
heat sink. This neutralized 8072 driver amplifier for 2 meters has
26 dB gain. The amplifier is built on a 7 inch rack panel.


8072. Max. ht. 2.26 inch, max. diam. 1.44 inch. Rated to 500 MHz.

Input circuit. Series-tuned half-wave tank; link coupling. Tuning and
matching controls on the front panel.

Output circuit. Series-tuned half-wave tank; link coupling. Tuning and
loading controls on the front panel.

Heater. Voltage adjustment at upper right.

Metering, with six meters:
Plate current, f.s. 500 mA, nom. 200 mA.
Screen current, f.s. 25 mA, nom. 8 mA.
Grid current, f.s. 5 mA, nom. 1 mA.
Heater voltage, expanded scale, 10 to 15 volts AC.
Power output, f.s. 250 watts.
Reverse power, f.s. 25 watts.

Screen supply. 300 volts, VR tubes, dropping resistor from
1500 volt HV supply for absolute screen protection.
All supplies built-in.

Power output: 200 watts.
Input power for full output: 500 milliwatts.
Gain: 26 dB.

Full description; in preparation.
The power supply, control, and protection circuits
are similar to those used in the HF transceiver. pdf

k5am home    amplifiers