VHF off 

1 September 2001 tbs.pm/1950

EDITOR’S NOTE: This article is more than 20 years old. The formatting may be strange, links broken and/or images missing. The text may have been superseded by subsequent events or later research.

We hear a lot of talk about digital, satellite, HDTV, widescreen, 16:9, pay-per-view, Digiboxes, gigahertz, and so on, and so forth. Television buzzwords and phrases, typical of the late 20th and early 21st century.

There was a time, nearly seventy years ago, when only the most eminent scientists and inventors would have understood some of it. All we had then was the promise of television, in two distinct forms: mechanical, with a maximum definition of 240 lines, and electronic, with 405 lines.

 

UK map showing ITV's VHF coverage in 1970

The ITA’s VHF network at its maximum extent in 1970

 

Considering the steady progress that television technology has made over the last twenty years – mainly in terms of cable and satellite, but more pertinently, in terms of choice – many have forgotten that all that was available to the average viewer in the UK for many years were three channels, BBC 1 and 2 and ITV, and the first and last of these were broadcast on 405 lines on VHF.

It was the Marconi-EMI system, developed in the 1930s and refined, first for ITA Band III broadcasts, for experimental colour services in the late 1950s, and then, finally, for 625-lines on UHF.

Later, the VHF transmissions were converted UHF signals sent out locally, as all origination at the studios was UHF/625 lines from around 1969. The move towards a universal standard was largely due to the wish to develop TV in parallel with other countries, not only to enable the use of common television hardware, but so programmes could be exchanged, sold and broadcast in other markets.

 

A flow chart showing the changes on 7 September 1969

7 September 1969: ITV switches from converting between 625 and 405 at source to only working in 625; the VHF transmitters will handle the conversion from now on.

 

The line standards were defined in the USA early on, by the National Television Standards Committee, who agreed on 525 lines. France went with 819 lines: and the rest of the continent went for a variation on each. 625 lines was considered by the Pilkington Committee in 1962 for the second BBC Television Service, especially with an eye to the future development of colour.

It could be said that this was the first nail in the coffin for 405 lines. As I recall, VHF Band I signals from Holme Moss on channel 2 were generally very good, but prone to high whistle at times. Occasionally there would be incidences of “sporadic E”, usually during the summer months, but at Christmas 1976 it was particularly bad.

Band III, Channel 9 (Winter Hill) was “smoother”, with less disruption to the picture. Channel 12 had better reception on BBC-1, but VHF TV sets had mechanical selector switches that were prone to slip, and the only way to get any improvement was to jam pieces of folded card behind the leading edge of the dial.

Bear in mind that unlike the coding/decoding pabulum we have now, all we had to receive this was a whip dipole hung from a rope in the attic and a concentric fine-tuning control to (hopefully) improve reception.

None of this took into account the effect of four high-rise blocks two streets away causing multiple ghosting!

 

A colourful map of the UK showing the 5 Band-I channels the BBC used

The BBC’s network of VHF Band-I transmitters by the early 1960s

 

In 1977, our family ditched the dual-standard set in favour of a sleek push-button UHF monochrome set. By this time, Dad and I had replaced the old dipole with a short Yagi array, horizontally polarized of course, and screwed to one of the crossbeams in the attic, so now we had three channels with excellent reception.

But, still I kind of missed the old VHF channels, and as a hobby of mine was to fix TV sets, I used to indulge in trying to see if I could still receive them. The old often-repeated joke is that with 405 lines, one could receive a signal with a piece of wet string.

I never tried that (and don’t try that at home, kids) but it was amazing that old bits of mains flex on a picture rail could produce a very acceptable picture, and even bring in the occasional DX picture.

January 1985 came around quickly. There had been noises about discontinuing the VHF services, and yet there was little fanfare about the very end. I saw “Coronation Street” on 2 January 1985, and the close of Granada that evening, but there was no actual announcement or curtain call.

The next morning, I switched on, and there was nothing. After all those years, the VHF Band I and III television broadcasts ceased. The reasons given by both the BBC and IBA were that the equipment was very old, nearing the end of its life, and that maintaining it was more of an art than a science.

Indeed, looking at the stills on Darren Meldrum’s site, it looks rather quaint and very much like a scene from Dr. Frankenstein’s laboratory.

 

ITA VHF and UHF comparative coverage maps from 1969

 

Since 1985, nothing televisual seems to be happening on Bands I and III in the UK, although there were a number of plans mooted. DAB radio can now be found on Band III, but that’s about it.

Some enthusiasts remain fascinated by the old system, and there are still those who try to get any parts for sets, video recorders and even studio cameras.

As I said at the start, there are so many definitions of television now, and the medium itself is taken for granted: but, while the old VHF system was maybe a little unreliable and prone to failure at times, it was, for many people, the first proper television system in this country.

Without its development and its later adoption by the BBC and ITA, we would not have had any television at all. And considering its discarding in favour of better technology, it might be gone, but it certainly is not forgotten.

 

You Say

4 responses to this article

Will Emslie 4 August 2016 at 9:49 am

In the Channel Islands, we didn’t get UHF 625 (or, thus, BBC 2 or colour reception) until 1976.

Although we lived on the opposite side of Jersey from the Fremont Point transmitter, I used to get excellent reception on a set I’d bought for my bedroom for £1 from a junk shop, using a makeshift dipole antenna made from speaker cable. I also used to get a fair picture from TF1 (which, as I recall, was the only French station still broadcasting on VHF) but with no sound because the French used a different system. I solved this problem by picking up the audio on a radio designed for listening to aircraft and the emergency services.

I would have been 12-13 at the time. And you thought you lot were nerds!

Louis-Marie Foratier 14 July 2017 at 3:34 pm

Hello from Nantes, in Southern Brittany, and thank you for your very interesting and useful details about 405 lines television.

I am French indeed and in April 1974 as a student, I spent a week with a Manchester family. They were proud of their brand new colour TV that had been installed besides the old 405-625 monochrome set.

In 1974 in France, TF1 was still using 819 VHF only, so I insisted to watch the 405 lines pictures. I knew it would be my only experience with this definition, but my hosts could not understand why : “Louis, you’ve got better pics… and colour on the new one !”

Indeed the 405 lines were terribly visible for someone used to 819/625 systems (although TF1 was already equipped with 625 lines and converting to 819 for its transmitters). My friends told me they were so used to this low definition, they were not paying attention to that for ages.

There was something very odd with this 405 set : it had a band III roof aerial towards Winter Hill for BBC1 and ITV, and an indoor dipole to watch some BBC1 Holme Moss outputs. The lady of the house showed me what she had accidentally discovered once while dusting the living room : she laid the dipole slant onto a small ‘toad’ armchair and turned the selector from Holme Moss channel 2 to another band I channel (I don’t remember which one, I guess it was 4 or 5 because ch 3 was used by high-powered Sutton Coldfield and ch 1 by Divis). Suddenly we could watch a good quality transmission from BBC Wales.

My hosts were sports fans (football of course, cricket etc) : this is why they had kept both sets to watch two different programmes simultaneously. So they were delighted to get BBC Wales because of its rugby matches. But despite all efforts to find another place, even on the roof, the dipole could only catch this channel from the armchair, without moving it of an an inch otherwise.

I presume there was a sort of ‘corridor’ between it and the welsh transmitter. They were the only house in their street with this peculiarity.

I unfortunately lost contact with them, and I am not sure they made experiments wit a UHF aerial on the ‘toad’ armchair after the 405 VHF closed down ten years later…

Russ J Graham 14 July 2017 at 6:18 pm

There are a lot of stories of people in the northwest of England who could get Welsh television. It wasn’t aimed at them, but there was a considerable overlap that was never shown on the maps for political reasons.

Being able to receive Welsh television had something of a social cachet in the 1960s and 70s – there were only three channels, so getting BBC Wales gave you a fourth channel – and the schedules between BBC-1 and BBC Wales were often quite different (and generally in English in peaktime too!). If you could also get the Welsh ITV contractor, who, again, had quite different schedules to England, you then had five channels – an amazing number in those days!

The reception of Welsh television in northwest England is so well known that many comedians from the area – like Victoria Wood – made jokes about it. Victoria Wood’s joke was that her grandfather had a metal plate in his head, but it wasn’t a problem – if they leaned him up against the back wall, they could get Welsh television.

Jon Charles 12 June 2020 at 11:51 am

We kept going until 1975 with 405 lines only – on a ‘portable’ Ekco set that seemed to weigh a ton. Because the cathode ray brightness on 405 was proportional to the signal amplitude, any passing car with a faulty condenser would create bright spots on the screen and a nasty noise on the sound. Added to that we had a radar establishment nearby and their rotating dish created periodic lines on the picture.

I was so excited to upgrade to 625 lines (and finally to get BBC2 and colour). I built a signal booster and tried to see whether we could pick up signals from other regions. Even though we lived in Worcestershire, I managed to get ITV Southern from Hannington which was brilliant because they were broadcasting Thunderbirds on Saturday mornings, whereas ATV wasn’t.

But when 405 lines closed down I did feel rather sad. It was the passing of a piece of TV history. It still warms my heart when I see an old band 1 or 3 aerial on a chimney!

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