The challenge of the backyard antenna

There were the days when you needed a long antenna, or aerial as we called it then. By long, I mean anything over 15 m, a length that was necessary both for broadcast radio and shortwave.

It was before the days of separate antenna tuners when, if you were working, say, 7 m, you tuned by tapping your own homemade coil to bring the set/antenna into approximate resonance. The tapping method was crude but effective.

Usually the coil was wound on the cardboard centre of a used toilet roll. Every so many turns, according to the wavelength you wanted, a loop was formed in the winding, which having been scraped clean of its shellac insulation, stood proud of the former and was ready for the wandering alligator terminal to link the coil into the rest of the circuit. As I say, crude but effective.

For a really professional job, the coil and former could be coated with varnish, which not only kept the windings in place but prevented damp getting into the cardboard. Not quite as convenient as a wavechange switch using commercial iron cored coils but a lot cheaper for someone on a very limited budget.

But it was the antenna that put up the greatest challenge. And that challenge was the length. However, I was fortunate to live in a house that had a back garden some 37 m long and ending in a thin line of very tall ash trees that were not only easy to climb but offered the perfect height and point from which to suspend an antenna.

So with my cohort, we scaled the ash until we were more than 15 m off the ground, tied a piece of thickish rope round the tree trunk, then a thinner piece of rope that that would pass through the eyelet of the insulator and finally the antenna wire itself, the end of which we tied in a secure knot.

The free end we ran towards the house and in particular to the pitched roof of a wooden shed which was the centre for all our experiments. We nailed a piece of timber to the apex of the roof and onto this we tied another piece of rope and an insulator and fed the antenna wire through a gap in the wooden walls to our workbench. (We were strictly forbidden to make any holes in the walls of the shed.)

This simple long wire antenna descended at quite a sharp angle from the tree to the shed but we had what we thought was sufficient height for all the broadcast and the more powerful shortwave transmitters.

But the antenna was only half of what we had to do. We also needed an effective earth or ground. This bothered us for some time until we decided on a length of spare antenna cable, one end of which we soldered to a flattened out and carefully washed ex-baked beans tin which we promptly buried at a depth of nearly a metre in the nearest soft ground. A thorough watering completed the task.

We knew the metal would not last for long, the tin was so thin, but we had no access to substantial copper rods, which would have been the alternative.

Testing the two systems on a single valve receiver was most satisfying. We were not sure how either would work or how well and if they would work together. We tried the antennas first and were very excited when a strong signal came through as we touched the wire of the antenna onto the coil. We were even more amazed when we connected the earth. What a difference that made.

In fact, our antenna and earth systems long outlasted the shed’s use as our interest temporarily waned slightly in favour of girls.

Who knows, the system may still be there today.