Wright's Aerials

Albert's Attic Gallery

"Yeah, Ten-Four Roger - the Handsome Hulk's got his ears on!"

Not as off-topic as you might think. These CB fanatics caused us some fine problems in the late 1970s and early 1980s. A lot of communal TV systems at the time had VHF TV aerials connected as well as UHF. This made them very susceptible to interference from strong 27MHz signals. Even with the VHF aerials disconnected, a spotty youth with a DV27 mounted on a biscuit-tin groundplane could cause havoc over quite a wide radius. These CBers were often invisible, since the DV27 and biscuit tin could be sitting on top of the wardrobe. The older, more hardened, Cbers frequently had 28-foot end-fed dipoles on top of precarious arrangements of scaffold tubes and guy ropes. After the first moderate gale the whole thing would be leaning at 30 degrees or so from the vertical, alarming the neighbours and giving rise to a transmission mode called 'wind modified polarisation'. In the house would be a 'burner', or 'footwarmer' - a crude linear amplifier of horrific power. With no filter between the burner and the aerial, every harmonic would be radiated at great strength. Some of the burners were capable of emitting 200W, so any nearby TV equipment would be completely 'wiped out'. EMC (electromagnetic compatibility) hadn't been thought of at the time, and TV sets would do strange things in the presence of strong RF fields. One well-known make would mute the sound in the presence of CB signals of even moderate strength. Even when we had absolutely no CB interference on the distribution system itself, a few of the residents' tellys would misbehave due to direct reception of the CB signal. Many a violent barney broke out on the streets between viewers and Cbers.

There was one individual, living in a flats complex, who was running a hire car business from home. He communicated with his cars using the CB handle 'Taxi man', and he transmitted a lot of power from a huge aerial on top of the building. The ground plane and counterweight was a motor bike! He made it plain to everyone that CB channel 20 was his exclusive property. Despite elaborate filtering at the communal system head-end, his transmissions affected every TV set on the estate. If he'd been a 'light user' it wouldn't have been too bad, but he was on the air every few minutes during the evenings, with almost continuous transmissions at chucking out time. The Housing Manager braved the rottweiler, with me lurking in relative safety along the walkway, and politely asked its owner to desist. This fell on deaf ears, so the council removed the aerial from the roof. It was replaced the same day, so the Radio Regulatory bods were called in. They confiscated all the equipment, but within a few days he was at it again. Just at the point when a riot seemed inevitable, fate took a hand. Our man was arrested for much more serious matters, and disappeared from view.

Another CB problem arose in a very poor TV reception area, where almost everyone had a masthead amplifier. Mastheads, being broadband devices, are easily upset by strong RF. In those days most mastheads were designed to work right down to 40MHz, which meant in practice that they would attempt to amplify 27MHz. The whole town was losing TV reception for periods of 20 minutes or so. A long time for a CB transmission, you might think, but this imbecile youth was playing LPs to his girlfriend, who lived 15 miles away! We found this one, thanks to the long transmission periods. No DF equipment was necessary. It was simply a matter of cruising the streets using a small screwdriver as a CB aerial. The kid desisted immediately.

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