When 27 MHz became legal in the UK another slice of bandwidth way up in the 900 MHz range was also made available for general use. At the time equipment was hideously expensive which left this frequency go mostly unused except by those with a more in depth knowledge of radio transmitters.
This UHF offering was where the UK government wanted CB to go originally before deciding on 27MHz which would have left users no choice but to continue operating on illegal imported U.S rigs.
The one problem with trying to transmit at 934 MHz is that signals can easily be blocked even by a few trees meaning if you have a great high location things are OK but anybody in even a modestly built up area is fighting a losing battle all the way.
Modern equipment at these frequencies is smaller and much more reliable than when the frequency was first granted to the UK but the band stayed almost dead until the legal status for transmitting there was finally withdrawn on 1 January 1999.
The License Free Half Way House
Since a lot of services that used to occupy frequencies around 450 MHz (mainly police) have sloped off into more secure networks like TETRA surely there is enough space to slot in at least 20 channels. This would give the UK a dedicated UHF CB service instead of the fudged system that has become popular on the low power output license free handhelds.
The design of license free radios doesn’t permit using any antennas better than the ones built into the radio, although we are sure that these restrictions have been “bent” (along with increased power output)to improve range or satisfy the experimenter in most CB radio users.
Whichever way you look at it trying to cultivate a UK UHF Citizens Band community on these radios is hampered from the start by the harsh limits imposed, besides these radios are used by business who would rather not have to fight to find a free channel.
A Model of a Successful UHF CB System
Australia has had a successful model of UHF CB running alongside the usual 27 MHz HF allocation for many years with the UHF being busier in some areas. Over time repeaters have been set up be groups of volunteers to extend the basic coverage of the UHF sets.
The Current Australian UHF band plan looks very similar to any amateur allocation with everything neatly separated into channels for simplex, repeaters and frequencies set aside for data modes.
UK UHF CB Equipment
Availability of equipment is huge with countless PMR sets that can easily be modified to operate on these frequencies and providing we are not saddled with a ridiculously low RF power limit they should be good to go.
A network of repeaters will extend communication range in the same way that amateur radio has been doing for years in the UK. Give the amateurs access to UHF CB and they will bring with them the wealth of knowledge that has built and maintained the many repeaters that make 144MHz/432MHz long range communication possible.
Even without the use of repeaters operating around 450 MHz has a lot of advantages over 27 MHz when it comes to setting up a station. Putting together a directional antenna with a good amount of gain is much easier (and smaller) at these frequencies than 27 MHz without the need for such a heavy duty tower to mount it on.
The space in the radio spectrum is there and at a more usable frequency than the first stab at UHF CB in the UK along with mountains of radios that can easily be tuned to work anywhere in that band but if that was all it took we would already have UHF.
Taking a look at the drawn out process the decision to allow the use of SSB in the UK turned into and it may give an understanding the nightmare trying to legislate a whole new set of license conditions is going to involve.
For a look at how UHF CB has evolved in Australia along with full band plans of frequencies used please visit www.uhfcb.com