ADJUSTMENT PROCEDURE-continued - TM-11-5820-670-300236

TM 11-5820-670-30

2-35. RECEIVER SENSITIVITY ADJUSTMENTS. (CONT)

ADJUSTMENT PROCEDURE (CONT)

9. Repeat step 5, and if signal still drops off, run signal generator up and down band to

determine if local oscillator is off frequency. This can be determined by hearing an audio

signal at a frequency other than 30 MHz. If this proves to be the case, perform local oscilla-

tor alinement (para 2-36), then repeat step 5. If signal drops off prior to 0.5 microvolt,

perform steps 10 through 14.

EL1AT245

10. With a small jeweler's screwdriver, adjust the 30 MHz variable capacitors on the A1100,

A1200, and A1300 modules for a peak in either sine wave or audio signal spectrum analyzer.

When a clear or maximum signal is obtained, lower rf attenuator of signal generator and

continue adjusting until no further improvement can be made.

11. Change frequency to 53.00 MHz and repeat step 10, tuning 53.00 MHz coils with a nonmetallic

alinement tool.

12. Change frequency to 52.00 MHz and repeat step 10, tuning 42.00 and 52.00 MHz coils with a

nonmetallic alinement tool.

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