OFF-ON-OFF TEST (three position, rotary switch)

OFF: Standby control panel OFF ON: Standby control panel ON TEST: - receiver squelch of the radio is disabled

• if background noise can be heard, the radio is operational

FREQUENCY TRANSFER PUSHBUTTON (momentary action)

PUSH (less than 2 seconds) - interchanges the active and standby frequencies on the display PUSH and HOLD (2 to 3 seconds) - causes the standby frequency display to disappear allowing the operator to change the active frequency setting PUSH and HOLD (2 to 3 seconds for the 2nd time) - restores the standby frequency display PUSH and HOLD (more than 7 seconds) - causes the transceiver to retune to 121.500 MHz, and display it in the top window. If nothing is displayed due to a display failure, any frequency can be selected knowing that every “click” on the large frequency selector knob will give 1 MHz incement and the small knob will give 25 KHz (or 8.33 KHz) increment

FREQUENCY SELECTOR (concentric, rotary action)

TURN - selects the desired frequency

• the outer (large) knob tunes the whole megahertz frequencies in increments of one MHz
• the inner (small) knob tunes the frequencies in increments of 25 KHz (or 8.33 KHz)
• clockwise rotation of either knob increases frequency and counter-clockwise rotation decreases frequency