For many years now there has been an unofficial CB frequency allocation on the license free 446 MHz band in the UK. Unlike our longstanding CB channels with a chance of working great distances at minimal power any signals at 446 MHz are going to be strictly line of sight (unless some sort of freak RF ducting occurs).

And with so many other private and commercial users utilizing this free resource for everyday communications setting up an enhanced radio system is going to pick up every shop within a few mile radius.

The 500mw output is the one restriction that really gets in the way when attempting to use 446 MHz at any meaningful distance and its interesting that many of the high end professional handhelds for this band are sold with full legal use international running at a more useful 4 Watts.

Staying Within the Law

446 MHz for CB radio type transmissions is well used in and around the big cities of the UK with many users taking the time to install more permanent radio setups that are easily going way beyond the legal restrictions laid out in the original license free agreement.

But when even running the existing half a Watt to an external antenna instead of using the one built into the handheld is illegal there is very little flexibility in the current system for any improvements while staying on the right side of the law.

The whole history of CB in the UK is littered with huge amounts of people willing to push past the official restrictions and equipment limits placed on us. We don’t see 446 MHz being any different when you consider all the radio enthusiasts who like to construct and experiment with transmitters.

Its interesting to remember that the UK government where against 27 MHz because of its long distance possibility and pushed hard to give UK CB users a frequency allocation at UHF where the power/antenna restrictions would have made it no more useful than 446 MHz is now.

Illegal 446 MHz Repeaters?

For many years amateur radio operators have understand the signal distance restrictions when transmitting at VHF/UHF frequencies and have built up an extensive network of repeaters that retransmit their signals over a wider area.

Even though we have never come across any rouge repeaters operating in the 446 MHz band its not like you have to reinvent the wheel to get one up and running quickly. Using the same tone access control as ham repeaters they could serve a reasonable area if positioned correctly with the only drawback being that because this isn’t a closed radio system the repeaters illegal use would be discovered very quickly through the interference caused to other users.

Maybe this has already been done somewhere and would be an interesting little project for those with the time and skills.


Without some relaxing of the law this does seem a bit of a step backwards for CB radio with so many technical problems and restrictions connected to the use of 446 MHz sets meaning it could only ever be a very localized service.

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