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Install a piece of insulated wire from J4 – Pin 2 – to Pin 1 of the panel mount power jack.
(J4 Pin 1 is square...Pin 2 is round)
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Apply 11 to 14 volts DC to the power input. The center pin is positive. Turn the unit on. The LEDs
should all flash once simultaneously.
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Check for +5.0 volts on the output of U2 (the 78L05). The output is the pin closest to the oscillator.
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Current draw should be around 8 mA (anything from 5 to 10 mA is acceptable).
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Set R23 (REV) and R22 (FWD) to the center position.
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Connect the transmitter and antenna (or dummy load) to the proper ports. With a voltmeter on test
point REV and about 5 watts applied and a dummy load or resonant antenna on the output, tune
C1 for minimum DC voltage. The voltage should be just about 0.0 volts (0.1 is OK). You MUST
use a 50 ohm load (either dummy or resonant antenna) to properly do the alignment.
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Again with 5 watts and with your voltmeter now on test point FWD, adjust R22 for 2.5 volts (2.0 to
2.5 is OK). This is a fairly course adjustment, so you do not need to be exact.
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Reverse the coax cables for the transmitter and antenna ports. With 5 watts and with your
voltmeter on test point REF, adjust R23 for 2.5 volts (2.0 to 2.5 is OK). This is a fairly course
adjustment, so you do not need to be exact.
If you cannot get 5 watts out of your transmitter, use 2 to 3 watts and adjust for 1.5 volts. Once
calibrated, the tuner is now ready to be placed on the air.
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