Amateur radio involves the use of radio waves to communicate with other amateurs around the World who happen to be on the air and within range.

With a mobile phone you do need to know the number of the person in order to make contact, and unlike the Internet there is a universal shorthand that can be used to communicate basic greetings and information independent of the local languages.

Communication can be made by voice, text, or with pictures. It brings together basic physics, electronics, computing, photography, and radio etiquette.

The communication range can be increased in a number of ways e.g.

  • Relaying the signal via the local repeater stations positioned on hills (50km range).
  • Relaying the transmissions via the amateur satellites orbiting the Earth (5000km range).
  • Bouncing the transmissions off the ionised layers above the Earth which are excited by the rays from the sun (up to 20 000km range).
  • Other methods include bouncing the transmissions off meteor trails in the atmospere, and even off the moon (780 000 km round trip!)

However the satellites are too low to be in stationary orbit and only appear above the horizon for 5 to 20 minutes at a time. The characteristics of the ionised layers above the Earth are very changeable depending on the frequency in use, the time of day, the season and the sunspot cycle.

More information can be found on the ‘TX factor‘ web site which contains a series of professionally produced high definition videos created by radio amateurs. They explore the history of amateur radio, rigs, antennas, operating modes, propagation, sport radio, training, club news, RSGB news, world news.

In addition, the ARRL ‘The Doctor is In’ is a bi-weekly podcast. It is hosted by Steve Ford, WB8IMY, and columnist Joel Hallas, W1ZR. The podcast is a lively 20-minute discussion of a wide range of technical topics and is available here.  www.arrl.org/doctor

Is it like CB?

It is a little bit, the best thing about the Citizens Band, and the main reason it was introduced as an alternative to amateur radio, is that the CB user needs little or no technical knowledge or expertise in order to successfully operate CB.

The UK Citizens Band can be used for work and play and is ideal where two or more people wish to keep in touch within a 6 to 12 km range. The conversations are free and it is possible to talk to numerous people in a group at the same time. It is a useful resource if you are involved in activities such as caravanning and camping clubs, off road driving, boating and fishing, or simply want to keep in touch with a group of friends or acquaintances.

There are 80 channels to choose from lying between 26.965 and 27.99125 MHz laid out in two blocks of 40. The upper frequency block was legalised in 1981 and the lower frequency block was added in 2006 (CEPT/EU channels) to harmonies with the European frequencies. The transmission mode is FM (narrow band frequency modulation) with AM (amplitude modulation) and SSB (single side band modulation) being allowed in the CEPT channels since 27/6/2014. The permitted powers are 4Watts FM, 4Watts AM and 12Watts SSB.

Unfortunately the CB frequencies require a relatively long antenna and tend to propagate poorly indoors and hence are mainly installed in vehicles. Many users of hand held radios have therefore moved to the PMR446 band.

PMR446 transceivers

The UK PMR446 radios provide 8 channels spanning the frequencies from 446.000 to 446.100 MHz and are also licence free. The much higher frequency allows the antennas to be reduced in size for hand held use. The radiated power is limited to 0.5 watts which gives a range of approx 1.5 km under average operating conditions.

Short range transceivers

General purpose UK short range radio devices use the frequencies between 49.82 to 49.98 MHz and are also licence exempt. They are limited to a radiated power of 0.01 Watts and are used by toy walkie-talkies, baby monitors, garage doors etc. Typical outdoor range is 50m.

Marine VHF bands

In contrast the marine band VHF (156-174 MHz) used by sea going craft and inland waterways in the UK are international standards. They require a marine radio operators VHF certificate of competence in order to get licensed. The radios can be used by boats at sea to contact the Coast Guards up to 50km away, or between yachts on the sea 10 to 15km away. More details can be obtained from the Royal Yachting Association (RYA).

CR – NCRC