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Periodic Maintenance
APPENDIX B - PERIODIC MAINTENANCE
EQUIPMENT CALIBRATIONThe SL40 design requires very few adjustments or calibration to be made. In fact, there are no internal manual adjustments.
REFERENCE OSCILLATOR
The reference oscillator frequency should be checked approximately every 3 to 5 years to ensure the units transmit frequency is within allowable tolerance.
The oscillator frequency can be checked by connecting the transmitter output through an appropriate load to a calibrated frequency counter. The transmit frequency should be within 15ppm of the selected channel frequency. Contact the Garmin AT, Inc. factory for instructions on adjusting the frequency if required.
CLEANING THE FRONT PANELThe front bezel, keypad, and display can be cleaned with a soft cotton cloth dampened with clean water. DO NOT use any chemical cleaning agents. Care should be taken to avoid scratching the surface of the display.
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