UHF RADIO

The Citizen Band Radio Stations (CBRS) is a two-way, short distance, voice communication service that provides a cheap, reliable means of communication.

The service operates in two frequency bands:

  • High frequency (HF) – (26.965 – 27.405 MHz) rare now days.
  • Ultra high frequency (UHF) – (476.4125 – 477.4125 MHz) our club radios.

UHF radios use Frequency Modulation (FM) and have become the preferred mode of operation for most.

In Australia, although there is no individual licence needed to use this equipment, it is still governed by the Citizens Band Radio Stations Class Licence and the Radio Communications Act. Under this Federal legislation certain channels have been reserved for specific use. Some other channels have also been designated for certain uses by general agreement.

CHANNEL and FREQUENCYDESIGNATED OR ACCEPTED USECHANNEL and FREQUENCYDESIGNATED OR ACCEPTED USE
 1 – 476.4250Duplex – Repeater Output41 – 476.4375Duplex – Repeater Output
 2 – 476.4500Duplex – Repeater Output42 – 476.4625Duplex – Repeater Output
 3 – 476.4750Duplex – Repeater Output43 – 476.4875Duplex – Repeater Output
 4 – 476.5000Duplex – Repeater Output44 – 476.5125Duplex – Repeater Output
 5 – 476.5250Duplex – Repeater Output  (Emergency use only)45 – 476.5375Duplex – Repeater Output
 6 – 476.5500Duplex – Repeater Output46 – 476.5625Duplex – Repeater Output
 7 – 476.5750Duplex – Repeater Output47 – 476.5875Duplex – Repeater Output
 8 – 476.6000Duplex – Repeater Output48 – 476.6125Duplex – Repeater Output
 9 – 476.6250Simplex49 – 476.6375Simplex
10 – 476.6500Simplex – 4WD – Convoy, Clubs and National Parks 50 – 476.6625Simplex
11 – 476.6750Simplex – Call Channel51 – 476.6875Simplex
12 – 476.7000Simplex52 – 476.7125Simplex
13 – 476.7250Simplex53 – 476.7375Simplex
14 – 476.7500Simplex54 – 476.7625Simplex
15 – 476.7750Simplex55 – 476.7875Simplex
16 – 476.8000Simplex56 – 476.8125Simplex
17 – 476.8250Simplex57 – 476.8375Simplex
18 – 476.8500Simplex –  Caravan and Convoy Channel 58 – 476.8625Simplex
19 – 476.8750Simplex59 – 476.8875Simplex
20 – 476.9000Simplex60 – 476.9125Simplex
21 – 476.9250Simplex61 – Reserved for Future Expansion
22 – 476.9500Data only – No voice62 – Reserved for Future Expansion
23 – 476.9750Data Only – No voice63 – Reserved for Future Expansion
24 – 477.0000Simplex64 – 477.0125Simplex
25 – 477.0250Simplex65 – 477.0375Simplex
26 – 477.0500Simplex66 – 477.0625Simplex
27 – 477.0750Simplex67 – 477.0875Simplex
28 – 477.1000Simplex68 – 477.1125Simplex
29 – 477.1250Simplex – Pacific (NSW) Hwy Channel69 – 477.1375Simplex
30 – 477.1500Simplex70 – 477.1375Simplex
31 – 477.1750Repeater Input71 – 477.1625Repeater Input
32 – 477.2000Repeater Input72 – 477.1875Repeater Input
33 – 477.2250Repeater Input73 – 477.2125Repeater Input
34 – 477.2500Repeater Input74 – 477.2625Repeater Input
35 – 477.2750Repeater Input   (Emergency use only)75 – 477.2875Repeater Input
36 – 477.3000Repeater Input76 – 477.3125Repeater Input
37 – 477.3250Repeater Input77 – 477.3375Repeater Input
38 – 477.3500Repeater Input78 – 477.3625Repeater Input
39 – 477.3750Simplex79 – 477.3875Simplex
40 – 477.4000Simplex – Highway Channel 80 – 477.4125Simplex

Channels 1 to 8 and 41 to 48 – Repeater Channels.  Press the DUPLEX button on your radio to use any available repeaters. 

Channel 22 and 23 – Data transmissions only (No Voice)

Channels 31 to 38 and 71 to 78 – Repeater inputs – Do not use these channels for simplex transmissions as you will interfere with conversations on channels 1 to 8 and 41 to 48.

Channel 5 and 35 – Emergency use only – Monitored by Volunteers. No general conversations are to take place on these channels.

As at January 2007 the maximum penalties for the misuse of the legally allocated CB emergency channels are:

  • For general misuse – if an individual 2 years imprisonment, otherwise $165,000 (a $220 on-the-spot fine can be issued in minor cases); or
  • For interference to an Emergency call – if an individual 5 years imprisonment, otherwise $550,000

If you are considering a trip into any remote area, then a UHF Radio is an important communications device to have. Besides the entertainment value, such as chatting with other vehicles, this radio can be a valuable safety tool.

Since UHF signals travel in a straight line, the terrain plays an important part in how well the signal is transmitted or received. For example, the transmission will perform quite poorly if the signal is blocked by hilly or heavily forested areas. On flat terrains such as open countryside, distances between 5 and 20km may be achieved. Distances of up to 100km can be achieved if one or both UHF CB units are elevated on say a hilltop. UHF signals are less prone to power line noises and also provide clear and crisp communications.

UHF radios provide FM quality, short range, line of sight communications and are excellent for convoys. In general, a UHF radio is not of much use in an emergency unless someone happens to be in range of your location – usually much less than 50km. Handheld units are useful because you can walk to higher ground and greatly extend the range if the vehicle is in a valley, or the battery is flat. Owning a pair of handhelds is also useful for bushwalking or in just about any situation you can imagine. In areas where repeaters are installed communication up to many hundreds of kilometres is possible. They are popular in pastoral country with stations operating on public and private repeaters.

Most, if not all modern UHF CBs can scan all channels and lock in on a channel when a signal is heard. This overcomes the problem of not knowing which channel the repeater or the homestead is operating on.

Repeaters

UHF repeaters are special transmitting/receiving stations that are usually located in high areas to allow extended coverage. These stations, which are usually owned by businesses, farmers and clubs, allow UHF users to use them to re-transmit their signal. It works when you press your microphone button with the “Duplex or Repeater” button selected also. You must transmit between channels 1 to 8 and 41 to 48 because the “Duplex or Repeater” selection will add 30 channels and will now transmit to channels 31 to 38 and 71 – 78 on the repeater. The repeater, which collects the signal on 31 to 38 or 71 to 78, then switches to its output channel 1 to 8 and 41 to 48 to transmit simultaneously to say another radio user who may be some distance away or out of line of sight for instance on the other side of the hill.

This can be hard to grasp but imagine a device that needs two frequencies to work and it needs to keep these input and output frequencies as far apart as possible to allow the simultaneous receive and transmit (i.e. 31 to 38 for the repeater’s input and 1 to 8 for the repeater’s output). The further apart these two frequencies, the easier it is to keep the transmitter circuitry from interfering with the receiver circuitry. Therefore, you should not transmit to a repeater on channels 31 to 38 or 71 to 78. Please respect the fact that repeaters are erected and maintained by private individuals and you should keep the usage relatively short.

Microphone Usage

When speaking on your radio hold the microphone approximately 15 centimetres from your mouth (not too close, not too far) press the Push To Talk (PTT) button, wait 1 second and then speak in a normal voice.

If your chosen channel is in use or another person is talking across your conversation just select another channel. Do not provoke troublemakers who may deliberately search out other people to provoke a reaction, just ignore them. 

Twin Rivers 4×4 Club Channel is:-   9 (Nine)

Twin Rivers 4×4 Club

We believe that to not just be the same old run of the mill 4WD club, that we need to connect with people. To embrace everyone, their interests, their talents and their experiences. We do this by sharing, by welcoming and by embracing every single member to our club, making them feel like they belong and feel they are supported along their 4WDing journey.

QUICK INFO

Monthly meetings at beenleigh bowls club, 11 Hanover st. Beenleigh, QLD.
secretary@twinrivers4x4club.com.au