a) If the dial pointer is to the left of the "5" marking, loosen the dial pointer drive arm
mounting screws and move the dial pointer drive arm base up until the dial
pointer is at the "5" marking. Retighten the screws.
ab)If the dial pointer is to the right of the "5" marking, loosen the dial pointer drive
arm mounting screws and move the dial pointer drive arm base down until the
dial pointer is at the "5" marking. Retighten the screws.
The preceding adjustment may affect the dial pointer setting at the zero marking. Repeat the
entire dial adjustment procedure as many times as necessary to obtain proper dial pointer
calibration.
Because the dial pointer is only a turns counter, it need not be exactly at a number
when the circular dial is at one of its five possible zero settings; however, the preceding
steps should permit fairly close calibration. Rotating the circular dial from a fully
counterclockwise position to a fully clockwise position will cause the dial pointer to go to
the left of the zero marking and to the right of the "5" marking on the plastic dial window.
These adjustments in no way affect frequency calibration, which depends only on the
circular dial reading.
ab.1.1. Dial Calibration
1. Zero beat the Main Tuning dial at 3.7 MHz.
2. Check for the calibrate signal and set the Zero Set dial. If the hairline is not close to the
window center, proceed with the following steps.
3. Remove the knob from the Main Tuning shaft without disturbing the zero beat setting.
4. Place a screwdriver through the hole in the dial escutcheon (directly above the main tuning
shaft) and into the LMO dial drive shaft.
5. Hold the LMO dial drive shaft on zero beat and loosen the setscrew in the circular dial. Turn
the circular dial until the 0 is directly behind the line on the zero set dial. Now retighten the
setscrew in the circular dial. Wrap tape around the Allen wrench so you do not short circuit
the pilot lamp socket with the Allen wrench.
6. Make sure the circular dial turns freely and the nylon spiral follower is properly engaged in
the spiral groove before proceeding.
7. Replace the knob on the Main Tuning shaft.
ab.1.2. Re-engaging the Main Tuning Pulley
The main tuning shaft may have become mispositioned as a result of removing the front
panel escutcheon, panel replacement, or adjustment attempts.
The pulley on the inner end of the main tuning shaft has a pair of beveled washers that
grip a metal ring on the inside of the circular dial. Turning the main tuning shaft causes
the beveled pulley to turn the metal ring on main tuning shaft.
Servicing Procedures Page 71
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