Motorola GP68, Руководство по обслуживанию

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March, 1997 6881086C09-O
4-5
GP68 Portable Radios Service Manual Radio Programming Information
Programming the GP68 Radio
A valid keypress tone sounds when the memory
channel data has been successfully copied over
to the MHz mode.
To Enable or Disable PTT ID Transmission
The radio transmits a programmable DTMF identification
code (unit ID), indicating which portable is in operation. The
PTT ID can be edited using the S
pecial Programming
Mode (see page 4-10).
During a conversation, the code is normally sent only on the
initial PTT press (unless PTT ID has been disabled). The
‘
TX ’ indicator lights for the duration of the PTT ID. If there
is no PTT or receive activity for 7 seconds, or if you change
the frequency or channel (or scan resumes), the PTT ID is
once again transmitted on the next PTT press.
NOTE
PTT ID can be enabled/disabled by pressing
and holding
. Upon pressing the button
you will hear a beep; hold the button down
until you hear a second beep, indicating that
the PTT ID status has been changed, then
release the button. When PTT ID is
disabled ,
the “dot” indicator flashes on the display.
To Change the Default Squelch Modes
Carrier squelch (CSQ), Tone Private-Line (PL) and Digital
Private-Line (DPL) operations are configurable on a per
channel basis. If an option board is installed, Signalling
squelch (SelCall) operation will also be configurable on a per
channel basis. If the Squelch Mode is set in Megahertz mode,
then it will become the channel’s default squelch mode when
the information is programmed into a channel.
To change squelch modes temporarily for a channel:
Momentarily press to change between CSQ,
Coded (PL/DPL) and Signalling squelch modes.
IMPORTANT
Squelch modes reset to the previous pro-
gra m med val ue s w h en th e ch an nel i s
changed. Squelch mode changes in MHz
mode are permanent.
When ‘ CTCSS ’ is off, the radio operates in CSQ mode. In
this mode, you will hear all conversations on the selected
receive channel.
When ‘ CTCSS ’ is on continuously, the radio operates in
Coded (PL/DPL) squelch mode. In this mode, you will hear
only those conversations on the selected receive channel
which have the same PL/DPL code as your radio.
When ‘ CTCSS ’ is flashing (which requires that an option
board is selected first via the Option Board Setup Mode), the
radio operates in Signalling squelch mode, and unmutes only
after a valid Voice Selective Call (SelCall) has been decoded.
The radio automatically enters CSQ mode for a period of
time. If there is no receive activity, the radio resumes Signal-
ling squelch mode and the LCD reverts to the appropriate
receive mode display.
When transmitting in Signalling squelch mode, PL/DPL is
transmitted if the Transmit PL/DPL code is non-zero (unless
the Transmit PL/DPL is programmed for ‘
000 ’). After PTT
is released, the radio automatically enters CSQ mode for a
period of time. If there is no receive activity, the radio
resumes Signalling Squelch mode. No visual indication is
given.
Refer to Receiving a Voice Selective Call in the User’s
Manual for more information on this squelch mode.
NOTE
A radio equipped with a Voice SelCall option
operating in the PL/DPL mode unmutes for
the correct PL/DPL code, or if a SelCall is
decoded.
To Select the Frequency Step Size
The frequency step size determines the incremental steps
that the receiver will take when you rotate the
Channel
Selector Knob , or when the radio is scanning the frequency
band.
The available frequency step sizes are 5, 10, 12.5, 15, 20, and
25 KHz.
Press and hold until the display indicates the cur-
rent frequency step size (takes about 3 seconds). For
example, the following display (Figure 4-10) represents
a frequency step size of 12.5 KHz.
Rotate the Channel Selector Knob to scroll through the
available frequency steps until the desired frequency
step size is displayed.
Figure 4-8 Changing the Default Squelch Modes.
A
SIG
B
SQL
C
LOW
N-DEL
D
SCAN
1
A
SIG
Figure 4-9 LCD Display for Changing Default Squelch
Modes.
Figure 4-10 .
CTCSS
1
C
LOW
2