NPX136D Series Panel Mount P25 VHF Transceiver
SM68 Installation and Operation Manual
Section 3 Rev: 1.00 Issue
4
Page 3-3
3.3.3
Controls and Indicators
ENG-FORM: 806-0114.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
Scan-Normal-Guard Transmit
Switch
Main RX/TX Annunciator
Main On/Off/Volume
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R:173.9975 067
Guard Volume Control
Guard RX/TX Annunciator
Guard Channel Switch
Display Switch Channel Switch
Squelch/Help Control Number Pushbuttons
3.3.3.1
Main Receive Volume and Power On / Off Control (MN)
The MN knob controls the main receiver volume; rotating it clockwise (cw) increases the volume, and
counterclockwise (ccw) decreases it. When rotated fully ccw past the detent, the NPX136D will be turned
off.
3.3.3.2
Guard Receive Volume (GD) (-070 only)
To increase the volume of the guard receiver, turn this knob cw; to decrease the volume turn it ccw. When
rotated fully ccw, the guard receive audio will be at the preset minimum level.
3.3.3.3
Main RX/TX Status Annunciator
The main RX/TX annunciator displays the RX (Receive) and the TX (Transmit) status of the main
transceiver. When transmitting, the LED will light green. When an RF signal is received that matches the
main channel's receive frequency, the LED will light amber. When idle (not receiving or transmitting), the
LED will be dark. The colour coding used for these functions corresponds to standard aircraft FM radio
conventions. Note that this is the reverse of standard vehicular conventions used with land mobile
equipment.
Note
: An NPX136D that is receiving may not produce any audio if the analog tones or digital squelch
mode present on the receive signal do not match those set for the current channel.
3.3.3.4
Guard RX/TX Status Annunciator (-070 only)
The guard RX/TX annunciator displays the RX (Receive) and the TX (Transmit) status of the guard
channel. When an RF signal is received that matches the guard channel's receive frequency, the LED will
light amber. When the main transceiver is transmitting on the guard channel, the LED will light green.
When idle (not receiving or transmitting), the LED will be dark.
