5. BASIC OPERATION
5.1 Turning NEPTUNE 100 on/off
To turn the transceiver on, rotate the PWR/VOL knob clockwise until it clicks on. You will hear a
beep (acoustic signal) and the LCD display will show the channel in use.
Important: when you turn on the radio for the very rst time, the display will show channel 16; while
usually, NEPTUNE 100 stores the last channel in use before it’s switched off.
To turn the transceiver off, rotate the knob counter-clockwise until you hear a click.
5.2 Volume adjustment
Bring the OFF/VOLUME knob rst to medium volume. Once the transceiver picks up a signal,
adjust the volume to a comfortable level. If no signal is picked up, use the squelch control as
described in the following paragraph and regulate the volume using the background noise.
5.3 Squelch Regulation
Squelch is used to eliminate the annoying background noise you hear when no signal is being
picked up. If the squelch is adjusted correctly, there should be silence in between calls as well as
a reduction in battery consumption. To regulate the squelch:
Rotate the 1. SQUELCH knob completely counter-clockwise until you hear the background
noise (if you don’t hear anything, increase the volume); RX will appear on the display.
If no signal is being received (only noise), slowly rotate the 2. SQUELCH knob clockwise,
stopping as soon as the noise and RX disappear stably.
If you regulate the squelch level too high (closed), you may hear only background noise or
intermittent discharges.
5.4 Selecting an operating channel
Press repeatedly the UP or DOWN buttons on the keypad or on the microphone to scroll through
the marine channels until nding the desired channel.
Channel 16 is dedicated to the emergencies, therefore we recommend not to use it for general
communications!
Channel 70 is dedicated to DSC communications.
5.5 Transmission and reception
Transmitting without a perfectly functioning antenna may seriously damage the
transceiver.
The PTT (Push-To-Talk) button is located on the external microphone of your NEPTUNE 100. To
transmit:
Ensure that no one else is speaking.1.
Hold down the 2. PTT button on the microphone. TX will appear on the Display. Wait for a
second, then speak in a normal voice about 5 cm from the microphone.
When you have nished, release the 3. PTT button: TX will disappear from the display. Now
NEPTUNE 100 is in receiving mode (silent and waiting for a signal) and will automatically
receive any communication.
