UHF CB Operating Frequencies

| febrero 7, 2019

UHF CB Operating Frequencies


The use of the Citizen Band radio service is licensed in Australia by the ACMA Radio communications (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 to 40 as well as the newer channels allocated from 41 to 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.


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


The AcMA has allocated channels 5/35 for emergency use only. channel 5 is the primary Simplex Emergency channel. Where a channel 5 repeater is available, you should select Duplex on cH 5.

NOTE: channel 35 is the input channel for the channel 5 repeater therefore channel 35 should also not be used for anything other than emergency transmissions.


AcMA regulations have allocated channels 22 and 23 for telemetry only applications and have prohibited the transmission of speech on these channels. consequently your radio has a transmit inhibit applied to channels 22 and 23.

In the event additional telemetry/telecommand channels are approved by the AcMA, these channels shall be added to those currently listed where voice transmission is inhibited. currently transmissions on channels 61, 62 and 63 are also inhibited and these channels are reserved for future allocation.



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