TV Aerials

Sometimes you catch yourself remembering…TL;DR unless you want a nostalgic trip back to sixties TVs.

Back in the 60s, as a boy I was fascinated by the magic of TV and how pictures could materialise from the air down strange shaped wire rods into a box and onto the picture tube. My Favourite Martian, the popular American TV series aired in the UK at the time,  took the V shaped 405 TV aerial further into fantasy.

TV Aerials inside and out (Practical TV December 1964)

Having a set top aerial was never a good plan compared with a large static one up on the chimney but our house was a bit different. Well not the house so much as the location on top of a hill in the suburbs of South London with nothing much in-between it and Crystal Palace where the nearest transmitter was sited. And the fact that most rooms had a TV in them although not all looked like TVs and many did not actually seem to work.

As kids we wanted to try and get them working, so the set top aerials came in handy to try our luck at picking up a signal. I suspect health and safety inspectors would have had a field day had they seen us playing with the TVs in this way but it’s amazing what we could learn. Some TVs looked like a bookcase with a small screen built in at the end of the top shelf with space books beside and below. I never did see it working as a TV though. Other table top models had rotary tuners that clunked into position to show BBC or ITV. Some had thin black tapered legs allowing the box to look suspended in air, often with an ornament on top along with the aerial.

Nothing was very easy or standard though. BBC was on a longer wavelength and needed the inner telescopic aerial rods extending to get a stable picture to watch the programme. I fiddled with horizontal hold to get rid of the zig zag lines and vertical hold to stop the picture moving up and down. Each hold had a separate control, usually a small knob hidden around the back, so you needed someone else to watch and shout ‘stop’ or ‘no’ as I twiddled or find a mirror so I could see the screen.

It might hold for a while, then drift or flicker as someone moved past the aerial. I noticed how the picture was better when the aerial rods were moved between horizontal and vertical and convinced myself at one time the horizontal holds were somehow related. They of course were related but not in the way I thought. I learnt how jumping to conclusions when trying to correct faults was all too easy. Dad would often put me right as I proudly told him how I’d got the TV working by aligning the vertical hold with the vertical aerial only to find out it was the signal strength that mattered and radio waves were polarised so needed aligning for best reception. Look at the aerials in the street he said, see how there’s a larger H for BBC and smaller picket fence for ITV. The fence points towards Croydon and the rods are aligned with the wave.

Changing from BBC to ITV needed retuning from 48MHz to 175MHz and I had to echo the set top to those in the street. But it was never that easy. Sometimes the picture refused to hold still and jagged lines or snow speckles appeared.

Some of our TV tuners had multiple channels and I was always hoping to pick up a Martian or satellite signal. I stared at the speckles sure I could see aliens or ghostly shapes. Ghosts were only too common on the set top aerial as it picked up reflections from multiple paths. A curious effect I noticed after watching the sparkles for a few minutes looking for a signal, if I looked away at the fireplace or chair they looked so sharp and clear. Somehow my vision was improved by watching TV I thought, quite the opposite of what we were told – don’t watch so much TV it will hurt your eyes!

There must be a good scientific reason why our visual system is fooled in this way but it’s not so easy to repeat the experience in the age of digital TV. Sparkles are replaced by the ever helpful ‘Signal low’ please check your aerial of some such.

You needed good eyesight to watch TV from across the room. The screen sizes were far far smaller than we have today. The iconic Bakelite Bush TV12 only had a 9 inch screen and later sets like an Ekco boasted a 15 inch tube if you were lucky. Makes your 50 inch 4K TV look positively enormous.

One of our TVs was hidden by doors on the front. The cabinet looked like a piece of furniture and plugged into the outside aerial so no giveaway V on top. But the picture was faint, the tube needed replacing and was not used.

I was lucky to have a KB TV in my room. It cost £1 at a jumble sale, a bargain I thought as it looked so space age. The front was nearly all picture tube with a light cream case wrap around. Controls where recessed to one side giving the KB a clean slimline look. OF COURSE It did not work but Dad soon repaired it and the picture quality seemed pretty good for a cast away.

Like so much tech, these curiosities would soon be rendered useless. A new higher definition TV system was being developed and a new channel BBC2 to launch. With an extra 220 lines the new 625 line system would use ultra high frequency UHF although still only black and white. We’d have to wait for the Apollo moon landings before seeing BBC in colour.

UHF needed new aerials with short picket fence not much higher than a rabbit. Dad’s collection of TVs were from his early TV and Radio repair business in Shirley, Croydon. He and his friend Bill set up the shop after the 2nd war. He collected sets that customers no longer wanted and he thought may be useful. Hence the bookcase TV that fitted in a bedroom.

But most of the TV shows and programmes I remember first seeing on the old 405 system. Shows like The Forest Rangers, Flipper, Batman and Ready Steady Go. The best programmes were on in the evening though. 7.25 we would line up to watch Danger Man or The Saint or Hawaii Five-O.

UHF sounded high tech and seeing 625 for the first time was so much clearer. Daytime TV did not exist so the BBC2 broadcast testcard transmissions to help the service engineers set up and repair the TVs during the day.

When production work in electronics stopped my father decided to retrain to service the new colour TV system – PAL (phase alternate line) that was starting to rollout. He joined a start up Spectra that saw the opportunity to be part of the rental model across London and the South East.

It was a busy time but it meant we now had access to the latest colour TVs as Dad’s spares were unloaded overnight to safety in the house. And the set top aerial had now shrunk to a squaerial.

But unlike the US TV system NTSC, (Dad called it never the same colour twice) our PAL system held on to the colour (chrominance) far better at low signal strength. I found how much more sensitive the aerial was to direction even with just two loops. You could point it around and see reflections where it was bouncing off objects rather than direct from Crystal Palace. The magic of analogue! With digital once signal to noise limit is reached and the error correction fails there’s nothing to see.

Colour TVs were much heavier due to the larger 3 gun CRT and I guess more lead in the glass to reduce the X-Ray emission from the higher 25kV EHT needed to pull the electron beams past the shadow mask. I remember the characteristic smell of ozone from some TVs. I noticed how the colour picture quality varied between manufacturers, GEC and Philips and the tell tail sign was convergence. I must have spent hours practicing to align our sets to minimise convergence errors.

Test card F, with the noughts and crosses in the centre picture, helped alignment along with the little girl’s skin tones for natural colour balance. Probably not a PC test card when think back it would have been better to have a range of skin tones.  Convergence was all about getting a linear alignment of the red, green and blue electron beams across the whole screen area. When out of alignment, instead of a white line on the test card you would see a red, green or blue edge or separate colour lines often curved away from their intended horizontal or vertical position. Many people may not even notice and on moving TV programme it could just appear as fuzzy coloured edges.

When the test card stopped it became almost impossible to set the convergence so Dad designed and build a cross hatch generator from some TTL logic gates and a TV tuner. This piece of kit produced a simple grid pattern, not as detailed as the test card but ideal for convergence as it showed up any misalignment over the whole screen. Sometimes the shadow mask could become magnetised and it needed a degaussing coil before converging.

Convergence controls were all hidden inside the TV. Mostly small potentiometers with red, blue and green coloured spindles or knobs to help identify which colour gun they affected. Some were simple magnetic rings around the neck of the CRT. Each control had a specific area or characteristic. Pin cushion for example. The bowed shape of a pin cushion could be used to cancel the opposite effect. There were hundreds of combinations of tweaks that you could make using these controls. It was easy to get it very wrong!

I do remember the Philips G8 series TVs having some of the best picture quality until the Japanese sets came along.The Philips had a characteristic set of six square push buttons at the top making it easy to switch channels quickly. Remote controls were not that common. Some sets had ultrasonic remote controls that just switched on or off.

The best colour TV we had was a Scantic. Probably late seventies. It had infrared remote control, that became a standard. It just kept going and sounded good too.  Made by Luxor a Swedish consumer electronics manufacturer. Forbes Rentals, then based in Purley, sourced the Scantic TVs i guess as an alternative to the GEC uk brands that had a far higher failure rate.