How can I improve my reception?

Short-wave signals travel from the transmitter to your radio by being bounced between the ionosphere (layers of electrified gas several hundred kilometres above the earth) and the earth's surface.

The gases in the ionosphere are often turbulent and this means that your reception can vary in quality between day and night, summer and winter and even during the course of a few hours.

Signals can also be affected by electrical storms, mountainous terrain and, in cities, by tall buildings.

Tips for best reception

If your radio is battery operated, you should ensure that the batteries are fresh, as reception will suffer if they are weak.

The loudspeakers in portable radios are often quite small, but sound quality can sometimes be improved by using an ear-piece, headphones or an external loudspeaker. Try placing your radio in different positions: reception is usually better by a window, especially one facing the direction of the transmitter. On each of our regional short wave frequency charts there is a Key to Transmitters which shows the location of the transmitter for each frequency.

Although placing the radio on a metal object (e.g. a filing cabinet) may help, very large metal constructions such as fire escapes and lift (elevator) shafts, etc. can cause interference. So can some domestic appliances, for example microwave ovens and computers.

Your aerial (antenna)

You should also experiment with both the length and the direction of the aerial of your radio. You may experience poor reception if you are trying to listen inside a steel-framed or concrete building, but if your reception improves when you take your radio to a window, an outside aerial could help.

Often all that is necessary is to wrap a piece of insulated copper wire a few metres long around the base of the radio's existing aerial. Hang the end of the wire out of a window, keeping it well away from metal objects and electricity supply cables.

As most good-quality portable short-wave radios are designed to be used without an external aerial, adding one can sometimes cause the radio to overload, so making a permanent aerial extension without experimenting first is not recommended.

Warning

It is important to remember about any outside aerial that high voltages can build up on it in thunderstorms. During a storm, you should disconnect the aerial from the radio and either earth the disconnected aerial inside the building or throw it out of the window.

How to make a simple aerial extension for short-wave reception

If you want to try making a more permanent aerial extension for your radio, this can be done with about 10 metres of insulated wire.

One end should be connected to the aerial socket of the radio. Most radios use a 3.5 mm jack connector plug, in which case you should connect the wire to the centre or tip connection of the plug and leave the outer or sleeve connection blank.

As much of the wire as possible should be suspended outside the building, ideally horizontally or at about 30 degrees above the horizontal, between the window and a support (for example, a tree). If this is not possible, then just hang it over the windowsill, away from metal objects and electrical cables.

The portion of the wire inside the building can pick up interference from domestic appliances, but this can be avoided by using coaxial or "screened" cable for this lead-in portion of the aerial. For this, the centre core of the coaxial cable should be connected to the aerial wire, with the outer braiding of the cable left unconnected.

At the radio end, the centre core of the cable should then be connected to the plug at the tip contact and the outer braiding to the sleeve. However, it is not a good idea to use more than a couple of metres of coaxial cable, as long lengths can affect the signal.