Uniden GMR648-2CK Radio User Manual

Choosing a Channel
Your radio has 22 channels and 38 CTCSS codes
you can use to talk to others.In order to speak to
someone, each of you must set to the same
channel and CTCSS code.
To choose a channel:
With the radio in "Normal" operating mode press the
ch/scan key and press the or key to increase or
decrease the channel number displayed.
Note: Channels 1-7 have an expectancy range of
up to 6 miles. Channels 8-14 have an expectancy
range of up to 3 miles. Channels 15-22 have an
expectancy range of up to 6 miles.You can know
which GMRS or FRS channel is active by the icon.
The icon indicates scanning GMRS channel,
and the icon indicates scanning FRS channel.
Choosing a CTCSS Code
Each of the channels 1-22 may have any one of
the codes, OFF or 1-38 selected.Code oF (OFF)
indicates no CTCSS code selected and your radio
can receive a signal regardless of the code settings
of the transmitting radio.
1) Enter the Menu.The CTCSS code on the LCD
display will appear.
2) Press the or key to increase or decrease
the code number displayed.You can also select
oF (OFF) at this stage.
3) Exit the Menu.
Talking on Your Radio
To talk to others using the radio:
1) Press and hold the
PTT button and speak in a
clear, normal voice about 2-3 inches away from
the microphone.While you are transmitting, the
icon will appear on the display.To avoid
cutting off the first part of your transmission,
pause slightly after pressing the PTT button
before you start talking.
2) When you have finished speaking, release the
PTT button.You can now receive incoming calls.
While receiving, the icon will appear on the
*Range may vary depending on environmental and/or topographical conditions.
15 GMRS / 7 FRS Channels
38 CTCSS Codes
Up to 6 Mile Range*
Internal VOX Circuitry
5 Selectable Call Tone Alerts
Backlit LCD Display
Optional Headset Accessories
Headset Jack
Roger Beep
1 Antenna
2 PTT (Push-To-Talk) Button
3 Monitor Key
4 Call Key
5 WX/Alert Key
6 Channel/Scan Key
7 Speaker
8 Headset Jack
9 Up Key
10 On/Off/Select Key
11 Microphone
12 Down Key
13 Battery Level Meter
14 Receive Indicator
15 Call Indicator
16 Scan Indicator
17 Channel Indicator
18 Alert Indicator
19 Weather Indicator
20 Transmit Indicator
21 Volume Setting Indicator
22 VOX Indicator
23 GMRS/FRS Indicator
24 Keypad Lock Indicator
25 CTCSS Indicator
26 Charging contacts
27 Charging LED
Congratulations on your purchase of the Uniden
GMR648-2CK (General Mobile Radio Service)
radio.This product is a lightweight, palm-sized
radio.Use it at sporting events to stay in contact
with family and friends, hiking, skiing, outdoors, or
in a neighborhood watch for vital communication.
This compact, state-of-the-art device is equipped
with many features.
Your package contains two GMR648-2CK radios,
two rechargeable NiMH battery packs (#BP38), two
AC adapters (#AD-0001), two charging cradles
(#RC6488), two belt clips and this reference guide.
You may operate the unit using the rechargeable
NiMH battery pack or 4 AAA alkaline batteries
(not included).The following optional accessories
may be purchased by calling the Customer Hotline
at 1-800-297-1023 (Mon-Fri 7 am to 7 pm,
Sat/Sun/holidays--except Thanks giving and
Christmas--9 am to 5 pm, CST). Use only Uniden
NiMH Battery Pack - #BP38
Charging Cradle - #RC6488
Headset - #HS2467
The GMR648-2CK radio operates on the General
Mobile Radio Service (GMRS) frequencies when
using Channels 1-7 and channels 15-22.You
must have a GMRS license issued by the Federal
Communications Commission to legally use
these channels. For licensing information and
application forms,visit the FCC online at:
www.fcc.gov/wtb/uls or call the FCC hotline at
1-800-418-3676. If you have any questions,you
can contact the FCC direct at 1-888-225-5322.
No license is required for operation on channels
8-14 or operation on any channel in Canada.
Your GMR648-2CK radio uses the NiMH battery
pack or 4 AAA alkaline batteries (not included).
To install the NiMH battery pack:
1) Make sure your radio is OFF.
2) Remove the battery compartment door by
pressing the tab at the bottom of the
compartment door allowing the door to be
3) Install the NiMH battery pack into the battery
compartment.Be certain to follow the instruction
written on the label on the battery pack.
In order to get the most out of your new radio, read this
reference guide completely before attempting to operate
the unit.
Turning the Radio On and Adjusting the Volume
1) Press and hold the sel/ key to turn the radio ON,
and increase the speaker volume by pressing the
key.To decrease the volume, press the key.
2) Press and hold the sel/ key again to turn the radio
Adjusting the Sound (Key Beeps)
Your radio emits a beep each time one of the keys (except
for the PTT button and call key) is pressed.To turn this
sound OFF, press and hold the call key while turning ON
the radio.Repeat this step to turn the sound ON.
Navigating through the Menu
To access the advanced features of the GMR648-2CK,
your radio has a Menu function.
Battery Charger
Battery Level Meter
Channel Monitor
Channel Scan
Keypad Lock
NOAA Emergency /
Weather Channels
Emergency Weather Alert
This unit has a battery level meter on the display to
indicate the status of the batteries.When the battery in
the unit is low, the battery level meter icon will
flash.Recharge the NiMH battery pack immediately or if
you are using the alkaline batteries, you must replace the
alkaline batteries in order to continue using the radio.
Warning! To avoid the risk of personal injury or property
damage from fire or electrical shock, only use the Uniden
accessories specifically designated for this product.
1) To enter the Menu, press the sel/ key.
2) Additional presses of the sel/ key will advance
you through the Menu until exiting to "Normal"
operating mode.
3) Other methods of exiting the Menu function are:
a. Press and hold the sel/ key again.
b. Press the PTT, mon, call, wx/alert, or ch/scan key
c. Wait 10 seconds until the unit automatically returns to
Voice Operated Transmission
Your GMR648-2CK radio is equipped with a user
selectable Voice Operated Transmitter (VOX) that
can be used for automatic voice transmissions.The
VOX feature is designed to be used with a headset
with a microphone.Transmission is initiated by
speaking into the remote microphone instead of
pushing the PTT button.
To select the VOX level:
1) Enter the Menu.Advance through the Menu until
vox icon appears on the display.The current
level (OFF, 1-3) will be indicated.Level oF (OFF)
disables VOX, while levels - set the
sensitivity of the VOX circuit.
2) Press either the or key to the desired VOX
sensitivity level.Use level 1 for increased
sensitivity to voice in normally quiet
environments, and use a higher level to reduce
undesired activation in very noisy environments.
3) Exit the Menu.
Transmitting a Call Tone
Your GMR648-2CK radio is equipped with 5
selectable call tones that will be transmitted when
the call key is pressed.
To select a call tone:
1) Enter the Menu.Advance through the Menu until
call icon is shown on the display.The current
call tone number ( - ) will be indicated.
2) Press the or key to increase or decrease
the number to the desired call tone.Each tone
will be heard through the speaker.
3) Exit the Menu.
To transmit the selected call tone, press the call
key.The selected tone will automatically be
transmitted for a fixed length of time.Call Tone will
be cancelled when the PTT button is pressed.
Channel Scan Feature
Your GMR648-2CK radio has a channel Scan
feature that allows you to easily Scan all 22
channels.When an active channel is detected, the
radio will pause on that channel until the channel is
clear.Then after a 2 second delay, the radio will
continue scanning.Pressing the PTT button while
the Scan is paused on a channel will allow you to
transmit on that channel.
To turn ON channel Scan:
Press and hold the
ch/scan key until the scan...
icon is displayed.The channel number on the
display will change as the radio rapidly cycles
through the channels.
To turn OFF channel Scan:
Press the
call, PTT, or wx/alert key, or
press and hold the ch/scan key for 2 seconds.
Normal NormalCTCSS VOX Level Call Tone Key Lock
OFF, 1-38 OFF, 1-3
2) To switch the Key Lock mode from oF (OFF) to
on, press the key.
3) To confirm the setting, press the sel/ key.
The radio returns to the "Normal" mode.
Note: If you exit the setting mode before confirming
your selection by pressing the sel/ key, the Key
Lock setting will be set to oF (OFF).
To unlock the keypad:
1) Press and hold the sel/ key to turn the radio
2) Press and hold the sel/ key again to turn the
radio ON.The keypad is unlocked.
Automatic Power Save Feature
Your GMR648-2CK radio has a unique circuit
designed to dramatically extend the life of the
batteries.If there is no transmission nor an
incoming call within 3 seconds, your radio switches
to the Power Save mode.The radio is still able to
receive transmissions in this mode.
LCD Backlight
The LCD Backlight will automatically turn ON when
any key (except the PTT button) is pressed.The LCD
display will illuminate for 10 seconds before turning
Monitor Mode Feature
Your GMR648-2CK radio allows you to listen for weak
signals on the current channel at the press of a key.
To turn ON the Monitor Mode:
Press mon for brief listening, the icon will
Press and hold mon for 2 seconds for continuous
listening.The receiver circuit will stay open, and
letting in both the noise and weak signals.
To turn OFF Monitor Mode:
mon to return to "Normal" mode, and the
icon stop blinking.
Roger Beep
Roger Beep is a BEEP that is sent to notify the end
of transmission (both PTT and VOX transmission).
Roger Beep can be heard through the speaker when
Key Beep is on.Roger Beep is transmitted even if
Key Beep is turned off.However, Roger Beep will not
be heard from the speaker.
To turn ON Roger Beep:
Press and hold the
key while turning ON the radio.
To turn OFF Roger Beep:
Press and hold the key while turning ON the radio.
If you use the rechargeable NiMH battery pack, two
GMR648-2CK radios can be charged by using the
charging cradle.
Make sure to turn the radio OFF before placing
the radio in the charging cradle.Otherwise the
battery level meter icon won’t indicate properly.
1) Connect the AC adapter (# AD-0001) to DC IN
9V jack and to a standard 120V AC wall outlet.
2) Set the charging cradle on the desk or tabletop,
and place the radio in the charging cradle with
the keypad facing forward.
3) Make sure that the LED illuminates.Charge the
battery pack for 16 hours and remove the radio
from the charging cradle after charge.
Note: The charge indicator LED will remain on as
long as the radios are left in the charger.
Installing the battery pack incorrectly will prevent
the unit from operating.
4) Replace the battery compartment door.
Key Lock
To lock the keypad:
1) Enter the Menu.Advance through the Menu until
the icon appears on the display.The current
Key Lock status oF (OFF) blinks on the display.