So where do all the rejected stations go?

There is an awful lot going on in the world of wireless, many thousands of transmissions all seeking our attention, some weak, some very strong, all likely to interfere with each other. By using an antenna that favours the frequencies we want to hear, it will go some way to discard those of less interest and reduce the chances of IP's - intermodulation products - spoiling the fun.

Down the GROUND wire into God's good earth. In many instances, this is via the earth lead in the mains cable and the plugs third pin.

THIS LEAD IS FOR ELECTRICAL SAFETY AND SHOULD NEVER BE REMOVED.

The problem is this path is shared by every other electrical appliance in the house, some of which will be fitted with suppressors which will now be using the same path to earth electrical noise. Nobody has ever taken the time to have a word with this interference, suggesting it should only go to earth without seeing your radios ground lead as a way into the set where it now finds itself in series with the aerial signal and so a part of it. Hence, more noise...

The answer is to add extra earthing as per the suggestions in the instruction manual. This will often shorten the earth path and make it more effective. After a wet Saturday afternoon doing manic Dracula impressions with large earthing stakes, you may feel your attempts at getting a good earth are better than the bloke who wired your house and a strong desire to cut the earth lead in the plug.

NEVER DO THIS. THERE IS A LEGAL REQUIREMENT FOR SAFETY EARTHING.

Some have found using a piece of coax left over from the antenna installation as an earth lead has some advantages.

A Co-Axial Earth

The wire core and the outer braid are connected together at the earth spike outside. In the radio room, only the inner core is connected to the GROUND point on the radio. As we have come to the sorry conclusion our earth lead is actually a part of our aerial, any interference picked up in the earth path is conducted to ground by the outer braid, leaving the centre core path "in the clear".

If we have problems with mains-borne interference, one answer is to allow our signal earth and our safety earth to ground in separate paths. If we are to maintain the integrity of our safety earth we can build in a high impedance "barrier" at signal frequencies in this path and take our station earth to ground from the radio side. This is nothing new. They were using isolating transformers as an end to common-mode noise back in the Thirties. These devices are now back in the accessory market. Forgive the wry smile of the old timer - the more things change to improve, perhaps, the more they stay the same.