Albert's Attic Gallery

When ITV started to broadcast in the mid-fifties everyone suddenly needed a second aerial. ITV used Band III, with alarmingly high frequencies around 200Mc/s. Many in the trade said it couldn't possibly work. The signal would only travel about a hundred yards from the transmitter, and if any signal did find its way to a receive aerial it would be lost on the cable. Of course, these prognostications were ill founded, and although the higher frequency signals had a more restricted range than the BBC channels ITV was soon a roaring success.
As an aside, it's interesting that the UK's second TV network used Band III rather than Band II. Of course the latter had been bagged for VHF FM radio and various utility transmissions, but I wonder if UK developments of the forties and fifties set the pattern for the world's use of the VHF bands for many years to come.
Many of the early converter boxes and Band III capable TV sets had separate aerial sockets for each band, but soon there was a need to combine the signals from the two aerials, and so the diplexer was born. A typical installation in an area of mediocre reception would have a Band I aerial, probably an 'X' or an 'H', and a Band III aerial of five or eight elements. Each aerial would have a separate downlead cable running to the diplexer, which would be fixed on the windowsill. It isn't difficult to combine 40 to 75MHz with 160MHz to 230MHz, so the diplexers were efficient. Ghosting received by the 'other' aerial was always a threat, but I can't remember it ever being much of a problem.

It was my job as a nipper to fit the diplexer while Dad was on the roof clamping the ITV aerial to the bottom of the 'X' aerial. The diplexer pictured was supplied with two long thin brass woodscrews, and there was a great temptation to bash them into the hardwood with a hammer. But they would bend, and then you couldn't pull them out of the diplexer.

There were no plastic cable clips in those days. As far as possible cables were secured to window frames or other woodwork using staples. If you had to fix to masonry, you had to use lead-headed wall nails. Half the time the lead (used to hold the cable) would fall off the nail as you banged it into the wall. The holes in the window frame were drilled with a brace and bit, and if you hit a nail it was a disaster. Sometimes customers would make the hole in the window frame using a red-hot poker. With repeated heating this would eventually burn a hole through the wood!

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