UHF CB mobile radio Australia
A new alternative to 27 Mhz AM / SSB communication on Citizens Band Radio in Australia!
This information is based on an advertising 6 page brochure by Philips TMC with editing updated by admin.
In June 1977 the Government introduced regulations to legalize and control the Citizens Radio Service.
These regulations (RB 14) stated that CB would operate exclusively on the 476 MHz UHF band from July 1982.
For the period from July 1977 to June 1982 both UHF and 27 MHz equipment could be licenced provided it met with the technical requirements and was operated within the regulations approved by the Government.
NOTE* Fortunately the government of the day
abolished this ridiculous idea and retained
HF CB on 27 MHZ,later type approving the US
40 Channel allocation on AM & LSB & USB which
exists to this time in 2022
The benefits offered to the community by CB Radio are now being recognized. Apart from the more obvious recreational and social aspects, CB is now being used as a communications medium for small business.
Another important area is in emergency communications during such situations as floods, fires, cyclones and motor accidents,
where normal communications facilities are either disabled or unavailable.
If CBers were permitted to operate in an uncontrolled manner confusion would result and negate the overall benefits.
It is evident that if anyone who felt like broad-casting could transmit on any wave length, with any power, at any time he chose, there would be so much confusion that no one (including emergency services) would have the benefit of radio communications.
The new regulations for Australia will overcome indiscriminate use of CB radio and make it a publicly controlled and a very workable two-way radio service for users.
Philips UHF CB – a first for Australia
The Radio Division of Philips-TMC which is part of the world-wide Philips group of companies has designed the first fully approved Australian made, 40 channel, UHF CB mobile radio
— The Philips FM 320.
It was designed by the same team that, in 1977, received an Australian Industrial Design Award for the Philips FM828 two-way radio.The FM320 uses similar technology and is equally outstanding in design and operation.
UHF CB has some notable advantages —
1. 40 channels available for use (more than double
the 18 channels allocated for 27 MHz CB radio),
which reduces channel congestion and provides
quicker and easier communication among CBers: |
2. Predictable range and channel re-usability.
3. High quality transmission and reception.
4. Small (15cm high), easy-to-install, pre-tuned aerial.
5. Minimal noise or interference to reception.
6. TVI (television interference) is virtually eliminated.
7. Creates negligible interference to the radio networks
of such essential services as police, ambulance, fire
brigades and life saving associations:
8. Meets the long term requirements of the Postal and
Telecommunications Department, up to and beyond
Yes the 476 MHz Quarter Wave UHF Antenna was only about six inches long and did work well on the chrome independent ground plane base on the boot of my Nissan Skyline seen here on SAU display at the 2007 F1 in Melbourne. But the 27 MHz HF CB base loaded Six foot ROYCE mobile whip worked skip all over the world from the Skyline! At this time in 2022 it is now mounted on my shed metal roof providing a great ground plane good enough to work stations in Nth & Sth America. Unfortunately I almost gave the Skyline away around 2008, but kept the antenna’s!
Let’s talk UHF CB
Established CBers are usually well informed on the workings of CB radio. But more and more people, while not yet CBers, are becoming interested in the local personal communication that UHF CB has to offer.
Some of the questions often asked are —
What is UHF?
The radio spectrum is divided into several sections —
LF — Low Frequency : Frequencies below 2OOKHz which is
below the AM Broadcast Band.
MF — Medium Frequency : 300KHz to 3000KHz
(3.0MHz) — includes the AM radio stations
500KHz to 1600KHz
HF — High Frequency : 3.0MHz to 30MHz
VHF — Very High Frequency : 30MHz to 300MHz
UHF — Ultra High Frequency : 300MHz to 3000MHz
These frequencies are also referred to by wavelengths, with the wavelength decreasing as the frequencies increase. In general terms the 27MHz band is referred to as the 11 metre band, the 145MHz amateur band as the 2 metre band, whilst the wavelength for UHF
CB is approximately 0.6 metres. Close to 70cm Ham Band
The different wave-lengths exhibit specific characteristics —
(i) in the HF band, signals radiate in all directions for
(ii) in the VHF band the signals are more dependent
on terrain and can be more easily directed,
(iii) in the UHF area the signals can be directed very
accurately and are virtually dependent on line-of-
Where does UHF citizen band radio fit into the radio spectrum?
The UHF part of the radio spectrum stretches from 300MHz to 3000MHz. The area of the frequency spectrum between 400MHz and 500MHz has been used internationally for years in two-way radio communications. Many government, taxi and transport
organizations use UHF for their mobile radio net- works, but one difference is that such companies generally operate base-to-mobile, mobile-to-base rather than mobile-to-mobile as with most CB radio.
The use of this area of the spectrum for two-way radio communications allows for better performance in terms
of range and lack of atmospheric disturbance.
The allocated band for UHF CB is the section between 476.425 MHz and 477.400 MHz at 0.025 MHz intervals.
Therefore, 40 channels are accommodated within 1.0 MHz. In 2022 we have 80 Govt authorised Channels at 12.5 KHz spacing between the original 40 Channel 25 KHz allocation.
AM and FM –
what do they mean?
A radio transmitter changes sound waves (your voice, for example) into radio waves by combining the audio frequency with the radio frequency carrier waves. When combined into one this is called modulated wave.
UHF CB radio uses FM, a frequency-modulated wave in which the sound changes the frequency of the wave. AM is an amplitude-modulated wave in which the sound changes the amplitude of the wave.
Although AM can cover great distances, static and man-made noises are also AM and can interfere with transmissions severely.
The advantage of UHF FM is its virtual noise-free reception.
A good example of the difference can be noticed during a storm when the AM radio in your home is filled with static whilst the FM sound coming from your TV set is not affected at all.
How does UHF FM transmission benefit CB?
The air is full of radio noise generated by industrial activity, motor vehicle ignitions, lifts operating, air-conditioning and the like.
At 27MHz this noise is at a very high level, and naturally a receiver detects this as well as an incoming signal.
At 476MHz the noise level is much lower as shown on the graph of electro-magnetic noise levels. With correct mute setting on a
receiver the major benefit of UHF FM is its virtual noise-free reception.
Furthermore, harmonic effects, which are interfering multiples of a transmitter’s own operating frequency, decreases significantly at the higher frequencies and, in the case of UHF CB, become unimportant, because of lower levels and location in the spectrum.
What about the range of UHF?
UHF waves travel in a straight line which means that the UHF CBer can predict fairly well how far his transmission will reach.
NOTE* Atmospheric “Ducting” can contribute to UHF radio
waves “Skiping” through various layers that exist in the
atmosphere that can at times act like a unseen giant Pipe.
This enables a UHF signal to be transmitted and received
vastly further than “Line of Sight”.
Many contacts have been made between 476MHz UHF CB stations operating standard “Type Approved” CB radios using Allowed
Five Watts of power output between Victoria And Tasmania and also South Australia with usually high gain verticle antenna’s.
The UHF CB range’ depends on the nature and terrain of the area where the radio is being used. In high-rise city areas, the mobile-to-mobile range is about 3-5km; in normal suburb areas 5-8km.
In some flat country areas it is possible to communicate at a distance of 15km or even further.
Was extremely happy that the FM320 was so light after back packing this lot up the back of Mt. William. Managed to talk to Geoff AX67 who was setup over in the High Country Snowfields about 300 klms away!
For base-to-mobile working the range is greater — depending on base station location.
Let us suppose we are communicating in an 8 klm radius in an average city area. That would make about 200 square kilometres of communication area possible. And since any one channel can be reused many times, communication possibilities in an area the size of
Sydney or Melbourne, for example, are almost unlimited. In the case of two signals both arriving at the same time, the UHF FM CB has a “capture” effect which allows the stronger of the two signals to prevail.
With HF CB 27 MHz signals the earth’s ionosphere tends to reflect these waves under certain sun spot influenced conditions.
This allows occasional transmission over an extremely long range (Hundreds to thousands of miles).
This phenomenon is known as “skip” ( or ‘DX’ ) and although it may be considered an advantage by almost all HF 27 MHz CB’rs, sometimes it only contributes to channel congestion by creating interference from distant stations. This can make local conversation impractical but is extremely rare and only happened in early Seventies High SunSpot 11 Year Cycle.
HF 27 MHz CB radio operators in Australia were being drowned out by American CB radio operators talking to locals unbelievably!
UHF waves do not normally “skip” in this manner and consequently the range is more predictable.
Focus on the Philips FM320
UHF CB mobile radio
The Philips FM320, in an impact-resistant matt black case, weighs less than one kilogram. It features Phase Lock Loop synthesizer and 5 watt RF output, the legal maximum allowable for UHF CB radio transmission. It has a 40 channel LED (light emitting diode) readout
channel selector with a flip switch that works with a forward and reverse action. By flipping the switch one way or the other, channels can be selected up or down the range.
The channel change control has the added feature of one channel at a time selection of continuous channel range. Pressing and releasing the switch steps up or down one channel whilst continuous ‘hold’ selects one channel at first and then three every second until released.
Each channel change is accompanied by a beep sound so that the operator/driver can keep track of the channel number without taking his eyes off the road.
For extra convenience there is also a remote channel change button on the microphone hand-piece.
Other features of the Philips FM320 are an S/RF meter indicating strength of signal received and transmitted, power, RX (receive) and TX (transmit) indicator lights, large volume control, mute switch and channel reset switch. The mute is a combined squelch /local
DX control; when set to high, the rig receives only strong signals and, when set to low, it catches fainter signals.
The reset control, when flicked up, automatically returns the selector to Channel 11, the traditional call channel.
If it is flicked down, it automatically selects a pre-set channel, and monitors it while the rig is on. ;
Positioning of the set itself is simple too, with its variable-position mounting bracket, and because it is so small can be mounted under or above the dash-board, in the centre console, or even in the radio J aperture in the dash panel.
The UHF CB FM320 is backed nationwide by Philips Service Centres and by dealers who are provided with comprehensive technical
training support. Consistent with this support and Australian manufacture is the assured supply of spare parts for years to come.
One of the most important sections of any communications system is its antenna or aerial. Unfortunately there is often insufficient
thought given to its placement and the equipment is unable to perform to its capabilities.
A basic mobile antenna length is dependent on the wavelength of the signal, and for optimum performance should be one quarter of
a wavelength or multiples of that amount. At 27MHz a quarter wavelength is approximately 3 metres, at VHF approximately half
metre and at UHF approximately 15cm.
From these figures can be seen the relationship between frequency and wavelength, as the frequency increases the wavelength decreases.
At UHF the shorter wavelength allows much more flexibility of antenna design and location, with the three most popular designs being
quarter-wave whip, coaxial dipole and centre loaded high gain types.
Whip type antennas need a ground plane for effective operation and centre-roof mounting is best, high-gain antennas still require a
ground plane but can be mounted less critically, co-axial dipoles are not dependent on ground-plane and can therefore be mounted in any location.
The antenna feeder cable is also important as any signal loss in the cable should be kept to a minimum for best performance.
Cable runs should always be as short as practicable and cables should always be joined by as few connectors as possible.
A quarter wavelength pre-tuned antenna is only 15cm high, its optimum length for effective transmission and reception.
The installation of this antenna is possible just about anywhere it is placed on the vehicle.
However, best results are always obtained from centre roof-mounting.
Because of the small antenna size many antenna options are possible and high gain models are available.
Another important organization is CREST, the Citizens’ Radio Emergency Service Teams,
which is an offshoot of the N.C.R.A. It provides a 24 hour voluntary monitoring service throughout Australia to assist in the preservation of human life, property and safety.
27.065 MHz has been allocated as the emergency calling channel for HF Citizens Radio.
A specific frequency for emergency calling within the UHF service will be announced by the Government shortly.
** EMERGENCY RPTR Channel #5 is officially allocated for this purpose by the Citizen Band Radio Stations Class Licence
The log books show that CREST is reducing reaction time between a call for help and the arrival of assistance from an average 17 minutes to less than 8 minutes. CREST monitors establish liaison with other emergency services — police, fire, ambulance.
CREST – Citizens Radio Emergency Service Teams. CREST is a voluntary emergency organisation. CREST commenced operations in September 1976 in most Australian capital cities and major towns. The initial role of CREST was to monitor the emergency frequencies on the Citizens Band Radio Service (CBRS), relaying calls for assistance from the public …
Philips-TMEC, the largest Australian manufacturer of mobile two-way radio equipment!
To be certain of high product performance, the Radio Communications Division of Philips- FMC in Clayton,
Victoria, makes a range: of high quality frequency determining quartz crystals and id filters, The experience and skill of its staff, the use of sophisticated equipment and the most advanced techniques ensure that Philips radio quartz crystals are equal to any in the world. The radio
crystals are just one important part of the know how which goes into the making of the FM320 UHF CB Radio
Philips-TMC uses and contributes to the great reservoir of technical knowledge of the Philips worldwide organisation. Proven overseas designs are often adapted to local conditions and requirements. Thus, equipment like the FM320, fully developed in Australia, has made use
of advanced international techniques.
Public acceptance of the newest member of the Philips product family, the Philips FM320 UHF CB Radio, has been enthusiastic.
If projections are accurate, one million Australians could be on air with CB by 1982.[Dont know if this became true but possibly?]
The Postal and Telecommunications Department is confident that the switch to UHF CB will bring many benefits to CBers.
In particular, and to society in general; there will be negligible interference to existing services, a more predictable range, and a larger capacity for more operators in a given area.
For technical enquiries write to:
Philips UHF CB
P.O. Box 308 Clayton, Victoria 3168
How to obtain your Government licence – NOT REQUIRED any longer!
People operating CB radio of any kind once must have had Government licence to do so, many years ago, but not now.
The CB Licensing Policy and Operations Branch Headquarters of the Postal and Telecommunications Department are in Melbourne Postal Address: G.P.O. Box 5412cc, Melbourne. 3001.
Telephone: (03) 602 0151
You can find the addresses of the State offices in other capital cities and the District Radio Inspectors’ Offices in the telephone book under the Australian Government listings.
You can obtain a licence application form (RB13) by writing to or phoning your nearest centre. The form should be filled in and returned with your licence fee of $25.00 for each CB radio you own.
CB Clubs and Associations
The rapid growth of CB users has of course stimulated organizations to help the CB radio operator.
The National Citizens’ Radio Association Inc. (N.C.R.A.) is recognized as the CBers spokesman and assistance bureau. This non-profit body helps CBers in many ways by e handling individual or club problems to do with interference and nuisance or technical difficulties.
1. lobbying for lower licensing fees.
2. representing CBers’ interests to Government and press.
3. “watchdogging”’ that the user gets the best possible price and service requirements.
4. ensuring that users’ manufacturing and equipment recommendations are passed on to industry.
You can find out where your nearest N.C.R.A. state office is by contacting The National Secretariat of the N.C.R.A.
P.O. Box E300
CANBERRA. A.C.T. 2600
Telephone: (062) 88 6849
NOTE* National Citizens Radio Association, Inc. Overview
National Citizens Radio Association, Inc. filed as a Domestic Non Profit Corporation in the State of Florida and is no longer active. This corporate entity was filed approximately fifty-five years ago on Tuesday, April 11, 1967 as recorded in documents filed with Florida Department of State.
477 MHz 80 CH.
|Channel||Frequency (MHz)||Description||Channel||Frequency (MHz)||Description|
|1||476.425||Rptr Output from #31||41||476.4375||Rptr Out from #71|
|2||476.450||Rptr Output from #32||42||476.4625||Rptr Out from #72|
|3||476.475||Rptr Output from #33||43||476.4875||Rptr Out from #73|
|4||476.500||Rptr Output from #34||44||476.5125||Rptr Out from #74|
|5**||476.525||Emergency Rptr from #35 **||45||476.5375||Rptr Out from #75|
|6||476.550||Rptr Output from #36||46||476.5625||Rptr Out from #76|
|7||476.575||Rptr Output from #37||47||476.5875||Rptr Out from #77|
|8||476.600||Rptr Output from #38||48||476.6125||Rptr Out from #78|
|22||476.950||Telemetry/Data (No Voice) **|
|23||476.975||Telemetry/Data (No Voice) **|
|29||477.125||Road Ch# (Pacific Highway)*||69||477.1375|
|31||477.175||Rptr Input to Ch#1||71||477.1875||Rptr In t0 Ch#41|
|32||477.200||Rptr Input to Ch#2||72||477.2125||Rptr In t0 Ch#42|
|33||477.225||Rptr Input to Ch#3||73||477.2375||Rptr In t0 Ch#43|
|34||477.250||Rptr Input to Ch#4||74||477.2625||Rptr In t0 Ch#44|
|35**||477.275||Emergency Rptr Input #5**||75||477.2875||Rptr In t0 Ch#45|
|36||477.300||Rptr Input to Ch#6||76||477.3125||Rptr In t0 Ch#46|
|37||477.325||Rptr Input to Ch#7||77||477.3375||Rptr In t0 Ch#47|
|38||477.350||Rptr Input to Ch#8||78||477.3625||Rptr In t0 Ch#48|
|40||477.400||Mobile Road Users Channel*||80||477.4125|
* This is a convention rather than an official allocation but worth adhering to for benefit of all.
Rptr = Repeater (DUPLEX) Press Duplex button on your UHF CB Radio and if you are on CH#5 and you press the transmit button on your microphone your radio will automatically switch to CH#35 and transmit. Any CH#5 Repeater which listens on the INPUT of CH#35 and receives your signal will immediately re-transmit what it hears you saying on its OUTPUT of CH#5 the EMERGENCY REPEATER.
This why you should not use the Emergency Repeater INPUT CH#35 in simplex mode as you may be interfering in Emergency communications without realising it as you are not hearing the CH#5 output. Also a good reason not to use any repeater input if there is any local repeaters on that channel you decide to use for no particular reason.
Please note that CREST – Citizens Radio Emergency Service Teams are monitoring CH#5 Emergency Repeaters across Australia in there own time and expense for the benefit of all on UHF CB Radio.
Note: Channels between 1 and 40 (except for the Telemetry / Data channels) are currently migrating from 16KHz to 10.1 KHz emission bandwidth. This allows 12.5 KHz channel spacing and provides the new channels from 41 – 80. The “Radiocommunications (Citizen Band Radio Stations) Class Licence 2015” permits equipment in use before the variation to continue to be used until and including 30 June 2017. Note also that channels 61, 62 and 63 have not been released for use at this time.