UNIDEN Model uh012sx UHF CB Radio
Operation
Selecting a Channel
Turn the Rotary Channel Selector to
select the desired
channel.
For your reference a list of the available
channels, corresponding frequencies and
guidelines for their use is printed on page
10. For Australia, Channels 05 and 35 are
reserved for Emergency Calls.
Transmitting
The uh012sx uses the 40 UHF-CB Channels
Select the desired channel. Press the microphone's PTT
button and speak normally into the microphone. Hold it
approx. 7cm from your mouth. Release the PTT button to
end the transmission and listen for a reply.
(Channels 22
and 23 are for telemetry and telecommand applications.
Transmit is inhibited on these channels).
Using Repeater Channels
UHF CB repeaters are used to retransmit or relay your signal. Repeaters will extend
the range of your radio and overcome the shielding effect caused by solid
obstructions. In normal Simplex operation, your radio transmits on one particular
frequency and receives on that same frequency. If there is a barrier that partially
blocks your transmitted signal, the probability of another radio receiving the signal is
very slim. Hills, tall buildings, metallic structures,...etc tend to act as a screen between
radios.
Standard Operation without the aid of a
Repeater Station.
Operation with the aid of a Repeater
Station (Duplex).
The signal coming from your radio is received by the Repeater Station and the
re-transmitted at the same time on another channel. This operation is called
"Duplexing".
For example,
CH01 on Duplex Mode will Receive on CH01 but Transmit on CH31
CH02 on Duplex Mode will Receive on CH02 but Transmit on CH32 etc...
If you transmit on CH01 Duplex mode, you are actually transmitting on CH31 the
repeater station down-coverts your signal and retransmits on CH01.
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