Using the VHF Transceiver
The first step in using the VHF transceiver is to make
sure the volume and squelch controls are set correctly for
proper reception.
1. Turn the VOL control clockwise to turn the unit on.
2. Rotate the SQL control fully counterclockwise. This
state is known as “squelch off”. Increase the volume
to achieve a comfortable listening level.
3. Slowly turn the SQL control clockwise and stop slightly
past the point where the noise disappears. This condi-
tion is known as the “squelch threshold”.
If the knob is turned past this point, weak signals
may not be received. No noise and no signals are received
until a signal with sufficient strength is received that
exceeds the squelch threshold. When the GPSCOM 170
is in receive mode, ‘RX’ is displayed in the VHF status
bar.
VHF Communication Pages
To move back and forth between the GPS and VHF
pages, press
C
. There are three com VHF pages in a
continuous loop: channel definition, com setup, and
memory bank. Press
C
to exit the GPS pages and
enter the com pages. Try scrolling through the com pages
by pressing
P
You can also scroll in the opposite
direction or return to a previous page by pressing
Q
.
The function of each of the com pages is discussed in
detail in the reference section.
The current channel will
always be displayed at the
bottom left of every page.
Using the VHF
Transceiver
Getting
Started
14
Important!
We strongly recommend
obtaining a marine radio
user’s guide such as
“Maritime Radio User’s
Handbook” published by
the RTCM (Radio
Technical Commission
For Maritime Services),
Washington, D.C., to
ensure proper radio oper-
ation and protocol.
Improper usage can result
in fines levied on
mariners by the FCC.
Squelch
Control
Volume
Control
Com Setup Page
Channel Page
Mem Bank Page
P
Q
170 manual pages rev D 9/21/98 9:23 AM Page 14