AMERITRON AL-572, Instruction Manual

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Ameritron AL-572 Instruction Manual
17
I
NTERCONNECTIONS
1. Connect the exciter's RF output to the "RF IN" connector on the rear of the AL-572 with 50
ohm coax. Use any good quality 50 ohm cable long enough to connect the amplifier to the
exciter. This amplifier connection uses a standard SO-239 female that mates with a PL-259
male connector on the cable.
2. Connect the existing station antenna system to the "RF OUT" connector on the rear of the AL-
572 with RG-8 type coax. This amplifier connection uses a SO-239 female that mates with a
PL-259 connector on the cable.
3. Shielded audio type cable with a standard male phono plug should be used to connect to the
"RLY" jack on the AL-572. This jack has positive 12 Vdc open circuit and supplies 100 mA
of current when pulled to ground. The relay circuit has an internal back pulse canceling diode
to protect sensitive exciter circuits from damage.
4. Connect a short, wide, and smooth ground lead from a good earth and RF ground to the rear
panel "GND" terminal. Avoid using braided conductors for ground leads.
5. The "12 V" connection on the rear panel provides 12 Vdc at 200 mA maximum to operate
external dial lamps or accessories such as the ATR-15 Antenna Tuner.
6. Connect the "ALC" jack to the ALC input of the exciter with a shielded cable and a phono
plug. The proper connection point on the exciter should be indicated in the exciter's manual.
The AL-572 ALC will operate with any exciter that uses a negative-going ALC voltage of up
to 10 volts.
Note: Transceiver ALC response times and ALC voltage requirements vary with different
manufacturers.
OPERATING INSTRUCTIONS AND GUIDELINES
F
RONT
P
ANEL
C
ONTROLS
"MULTIMETER" Switch
This four position switch selects either the plate voltage (HV) of 0-3500 volts, the reflected peak
envelope power (REF) of 0-500 watts, the ALC detector output voltage (ALC) of 0-35 volts, or
the approximate ALC grid current threshold (ALC SET) of 0-350 mA. See the "
Metering
Functions
" section on page 9 for more details.
"OFF-ON" Switch
This switch turns the main power off and on. When this switch is placed in the "ON" position
the fan should start, the meters should be illuminated, and high voltage should appear.
"STBY-OPR" Switch
This switch disables the amplifier's internal antenna relay. In the "STBY" position the amplifier
is bypassed without turning the tube's filaments or the power supply off.