GME TX675TP User Manual
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i n s t r u c t i o n m A n uA l
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IMPoRtAnt InFoRMAtIon ConCeRnInG
UHF CB RADIo
the use of the citizen Band radio service is licensed in Australia by the AcmA
radiocommunications (citizens Band radio stations) class licence and in
new Zealand by the ministry of Economic Development new Zealand (mED).
A General user radio licence for citizens Band radio and operation is subject
to conditions contained in those licences.
the class licence for users and equipment operating in the cB/Prs 477 mHz
band has been amended. this radio meets the new 80 channel standard.
in simple terms the same amount of spectrum is available; however, radio
transceivers can now operate in a narrower bandwidth and hence use less
spectrum. these radios are generally referred to as narrowband or 12.5 kHz
radios. By using 12.5 kHz channel spacing instead of 25 kHz, the 40 channels
originally allocated can now be expanded to 80 channels thereby doubling the
channel capacity and relieving congestion in the uHF cB/Prs band.
original 40 channel wideband radios will continue to operate on the original
40 channels, however they will not be able to converse on the newer channels
41 – 80. the newer narrowband radios will be able to converse with all older
40 channel wideband radios on all channels 1 – 40 as well as the newer channels
allocated from 41 – 80.
the mixing of narrowband and wideband radios in the same spectrum can
cause some possible operating issues of interference and varying levels of
received volume.
Possible issues
when a new narrowband radio receives a transmission from an older wideband
radio the speech may sound loud and distorted – simply adjust your radio volume
for best performance.
when an older wideband radio receives a signal from a new narrowband radio,
the speech may sound quiet – simply adjust your radio volume for
best performance.
Depending on how close your receiving radio is to another transmitting radio,
there can be interference from the transmitting radio if it is using a channel
adjacent to the channel you are listening to. simply try going up or down a few
channels from the currently selected channel.
the above situations are not a fault of the radio but a symptom of operating
wideband and narrowband radios in the same bandwidth. this possible
interference will decrease over time as the population of wideband radios ages
and decreases.
Further information and updates are available from the Australian
communications and media Authority (AcmA) at www.acma.gov.au and the
ministry of Economic Development (mED), radio spectrum management at:
www.rsm.govt.nz