.
Setting CTCSS to ‘00’ allows the radio to receive all transmissions, regardless of CTCSS tone.
VOX
NOTE: The VOX feature will work the same without a headset by following these instructions
but do not plug in a headset. Speak into the ATT650/655 series microphone and the transceiver
will transmit and switch to receive after you stop speaking into the microphone. The transceiver
behaves exactly like a speakerphone in this mode without the headset.
The voice activated transmission (VOX) function allows your voice to activate the PTT
automatically. This may be useful when the radio is used with an optional hands free headset.
To access the VOX menu, press [F] in the channel selection mode until ‘Uo’ appears and VOX
option flashes. Press the [ ] and [ ] to select from Hi, nr, Lo or OFF. Press the [M] button
momentarily to confirm your selection. The high, normal (nr) or low setting determines VOX
response sensitivity. Select Hi when in a quiet environment and Lo for a noisy environment
Transmission Power
The transmission power is internally set to low power on channels 8 to 14, and is high on the
other channels to comply with FCC regulations for power limits on FRS and GMRS channels.
Channels 1 to 7 are shared between FRS (low power) and GMRS (high or low power) , 8 to14
are exclusively FRS with only low power allowed, and 15 to 22 are for GMRS use with high or
low power permitted.
Note: The output power is automatically selected depending on which channel you are using
and cannot be changed by the user.
Notes for good communication
Your radio’s channels are shared on a ‘take turns’ basis. This means other groups may be
talking on any of the channels. A common code of courtesy is to switch to another vacant
channel and not to attempt to ‘talk over’ or interrupt someone who is already using a channel.
Your radios have been designed to offer the best performance and transmission range. To avoid
interference, it is recommended that you do not use the units within 2m (6 feet) of one another.
For best transmission results, always keep the radio 10~15cm (4 –6 inches) away from your
mouth. Speak slowly and clearly into the microphone and avoid releasing the PTT until you
have finished speaking.
Care and maintenance
Clean your unit with a damp (never wet) cloth. Solvent or detergent should never be used.
Avoid leaving your unit in direct sunlight or in hot, humid or dusty places.
Keep your unit away from heating appliances and sources of electrical noise such as fluorescent
lamps or motors.