UHF TV in England...
 

Up till 1964 there was no UHF TV in England, you had BBC on Low band & ITV & a (very) few BBC TX's on high band, all using 405 lines with positive video modulation & AM sound. In 1964 BBC2 (the original BBC was then called "BBC1") fired up on UHF on a different system using 625 lines, negative video modulation & FM sound, so a simple UHF to VHF converter wouldn't work. if you wanted to watch BBC2 you needed a new dual standard TV & a UHF antenna, most people didn't bother with BBC2....

Fast forward to November 1969 when BBC1 & ITV fired up on UHF 625 lines joining BBC2 with colour. (BBC2 had been in colour since 1967) About 60%/70% of the population could now get all 3 channels on 615 lines UHF from the get go & people started to buy/rent 625 lines UHF black & white or colour TV's; (You could then get old 405 lines VHF only TV's free or for very few pounds) Over the next 2/3 years dozens of 625 lines UHF TX's fired up around the country & almost everyone could now get 625 lines UHF if they wanted & by the mid 1970's England had become a de facto all UHF country, very few people now watched 405 lines VHF TV. The 405 lines VHF TX's were kept going till the early/mid 1980's but very few people actually watched them & no one seemed to notice as the last ones were turned off in Jan 1985...

Nowadays all the Digital TV TX's are on UHF & you get dozens of channels, some of them in HD...

This month in the UK we celebrate 50 years of colour on what were then our 2 main channels, BBC1 and ITV. I will be part of the team bringing "Southern" outside broadcast (remote) truck to an event in Birmingham in the English midlands on Saturday 16th November.

https://becg.org.uk/event/colour-tv-comes-to-town/

On the Friday evening before the event we hope to be going on air live from the truck on ITV news.

Any chance that some of this will end up on the internet where we in the U.S. can look at it?

I'm presuming that England (& the rest of the UK of course) was the first de facto (then de jure in 1985) UHF country in the world? I know some areas of America & Canada were known as UHF islands as there were no VHF TX's in range, South Bend Indiana was one AFAIK, there must have been others as well...

There were some very remote parts of the UK that couldn't get UHF TV right up till VHF close down in 1985 & had to watch old 405 lines VHF TV's that'd only get BBC1 & ITV up till then, I presume they'd have been TVless till satellite TV fired up in the late 1980's. Heard they'd get friends/relatives to record their favourite TV shows for them..

We had UHF-equipped sets in Spain in 1963 (I'm looking at one right now) though according to the official history of TVE, they didn't start broadcasting on the UHF band until 1966 with the introduction of TVE2. I cannot believe they were building and selling UHF-equipped sets with nothing to receive for three years before the TVE2 launch, so maybe there is some discrepancy in the history.

Not too long ago, the US had a few DTV channels on the high band VHF. Through this year, all the VHF DTV channels were eliminated. Just recently, all the DTV channels were reassigned to different locations on the mid-UHF band.
I really like the quality of the DTV reception, it's either perfect or nothing at all. :thmbsp:

Sorry, I think you may be confused.

Not only will DTV transmitters continue to broadcast on the VHF-High band, there will be more transmitters on VHF - not only VHF-High (Band III), but also on VHF-Low (Band I and Band II) as well.

Soon, ALL US broadcast TV will be on channels 36 and below.

The spectrum auction paid TV stations to switch from UHF to VHF (low or high), switch from VHF high to VHF-Low (Including the legendary public TV station
WGBH), or give up their spectrum altogether (and even these have the option of remaining licensed TV stations, including must-carry status on cable and satellite providers, if they could find a transmitting station that would sell or donate some of its bits).

Locally, WTLW in Lima, Ohio, moved from channel 44 to channel 4.

Lima, Ohio, huh ?!? Sure do wish Fair Radio still sent out catalogs like they oncet did.. For all us wannabe Mad Scientist types, a new Fair Radio catalog was almost as good as Christmas...I even managed to "Steal" a '55 COLLINS R-390A that had all the correct Collins paint daubs from under Phil Sellati's nose...Rick Mish offered me $5K, or 2 of his "Museum" grade restos for it... Ahh, the Good ol' Daze...

In the UK too. It's called 700MHz clearance: https://www.freeview.co.uk/corporate...0mhz-clearance

I'm probably just thinking of this area! I don't see any of the DTV stations in the VHF region, either low or high. :scratch2:

Wow, you are lucky, the VHF channels seem to be more difficult to receive in many areas. What is your general area?

jr

We've had a channel 9 physical around here since the digital start.
Its not hard to get at all. Lots of people get it on a UHF double bowtie antenna.

High VHF would be really easy, even compared to UHF, to get if the FCC assigned just a bit higher power. Low vhf would need substantially more
power from the power line than analog, or more bays, to get reliably
digital.

I think "substantially more power from the power line than analog" is not quite right, since the assigned power of the digital signal was significantly less than an analog station on the same VHF channel. "Substantially more power than the current digital transmitter" is correct.

Hi VHF example: WLS-TV in Chicago, RF channel 7 for both analog (55 kW ERP) and digital (4.75 kW ERP).

Low VHF caps: analog 100kW; digital 10 kW or 45 kW depending on location. In general, the licensed digital power is adjusted downward to solve interference issues.

High VHF caps: analog 316 kW; digital 30 kW or 160 kW depending on location. In general, a particular station's licensed digital power is adjusted downward to solve interference issues.

What I observed on visits to England in 1976 and 1980, all UHF yagis even in the most seemingly remote areas. In all kinds of mountings, in different directions from the same chimney.
Some VHF-Hi yagis were observed and those classics that were just an "X" for low VHF or FM (both- I was told) About every other place we stayed had something like a Philips 20-inch color with 4-presets, no knobs anywhere.

There was no "channel 4", only BBC1, BB2 and ITV. Maybe 4 came along by 1980 in the bigger cities, there were Philips BW sets loops and set-top zig-zag helicals, one of which I was given as a token for repairing some electrical items with fused plugs where we stayed. The older folks seemed rightly afraid of 240 V and were glad to let some kid sort it out for them.

A few years ago, while looking on a UK website called "antenna hacks", I learned much about our evolving band changes here in the US notably the UHF band has shrunk, with fewer active transmitters in any given area. The UK's classic UHF antenna solutions with several bands and narrow-spectrum yagis are a good fit for most of the US, at least where UHF predominates.

A friend of mine from TV servicing past predicted we would still need a broadband antenna to get everything available, even after I and most others were sure VHF low was gone!

First WPVI-6 in Philadelphia remains on 6 with with other new VHF-lo channels, WDPN 2 in Phl and WACP 4 in S. Jersey and now a channel 5 in lower Delaware! One Channel Master 1160 still gets them all, no matter how repacking affects them :)

In the UK, Channel 4 started in 1982. It was rolled out nationally over a short timescale. The UHF channels had been assigned as part of thejoint BBC/ITV band planning process which gave 4 channels to each transmitter. The aim was to achieve full national coverage (99% of population?). Channel 5 was shoehorned in much later. A bit of a bodge job, with large areas not covered.

The 405 line services in Bands I and III (Low and High band VHF) were finally tuned off in 1985. These bands have not been used for TV since then. There are still a surprising number of antennas visible.

My residence is 41 miles north of Milwaukee, WI. My workshop is 26 miles north, both a short distance from Lake Michigan.

WIWN (68 virtual) is transmitted on ch5, and WMVS (10 virtial) is transmitted on ch8...are these out of range for you? :scratch2:

jr

I have a beautiful collection of vintage spanish TV sets. I don`t know
a pre-1966 TV with a factory build-in UHF tuner.
I have closeby all schematics of spanish TV sets and collected spanish
TV guides.
When you look at the history of Spain you have to realize that Spain was
a poor country.
To sell TVs in higher numbers many of these sets had small 47 cm tubes,
a good way to sell for low budget.
I have a 1963 spanish made Telefunken TV set, looks like the german
original, but is shrinked to a 47cm diameter CRT and without UHF!
I am not sure about Philips, have to check that at schematics.
But spanish TV sets had no UHF before the official start in 1966.
One of my 1959 sets has an after market UHF tuner.

Regards,
TV-collector:stupid:

In the early 1970's my parents bought a Sony KV1800: It only had a UHF rotary tuner (which were very unusual on English sets) but there was a square blanking plate just below where I presume a VHF tuner would have gone if it went anywhere else in the world but England. Most English made single standard 625 kines sets back then had push button UHF only tuners with 4 buttons that could tune to any UHF broadcast channel, they were marked from top to bottom: BBC1, BBC2, ITV & the fourth button would on some sets say ITV2, (there never was an ITV2 back then, there is now though) & some with just a * on it. People living in ITV overlap areas could receive an alternative ITV station & this was tuned in on button 4. When channel 4 (channel 4 was the station name not the broadcast channel, it was broadcast from hundreds of transmitters on nearly all UHF channels) fired up in 1982 that was then tuned to button 4, people who had previously tuned it to another ITV TX were then chockered. Later sets had 6 or 8 buttons on their tuners, then came remote controls...

Is the UHF in Great Britain grouped into "bands", band 1 being the channels 14-30, band 2 is chs. 31-40, etc?

It seems that a broadband UHF antenna like a simple bow-tie, so common in North America since the UHF band brought TV reception to smaller cities in 1952, is not the go-to UHF in the UK.

There seemed to be more Yagis, selected bands instead of the entire former spectrum.

I have tested over a dozen UHF-only antennas of several types, many vintage and some new ones. Often wondered if "tuning" them to the present spectrum of 470-614 Mhz would make them even better. :scratch2:

Looking at 50+ year old antennas still on houses, gives some clue to what works in that location. Many of those cute little imported antennas with built in rotators would do nothing in some of the locations I see upstate in wooded mountain areas, but the simple 4-bay was a miracle to many trying to pull in UHF and a Parabolic to those most desperate for reception.

Example: 4 and 8-bay bowtie arrays work better in scattered signal locations such as behind evergreen trees BUT a Yagi or corner reflector bowtie will still have the edge on a weak signal with no close-by obstructions.

UHF in the UK is Band IV for channels 21 -37, Band V for channels 38-68. Antennae are grouped according to which set of channels your local transmitter uses. Wideband antennas are common but give less gain. Most antennas are some variant of a multi-element yagi. Log periodic antennas seem to be getting more popular. They give a flatter response and cleaner polar diagram than a yagi.

For those that are interested in UK/European UHF Antennas/Aerials.

I just had my UHF TV aerial changed, there was water in the cable. it was one like the one below. It was wideband channels 21-68. The new one is a log periodic UHF 21-60 like the one below. I live about 25 miles from the Sutton Coldfield transmitter. Each multiplex is output at 200kw, both new and old require a mast top amplifier and power supply in the house.

Interestingly, modern aerials use F-Connectors (like satellite TV) and not traditional aerial plugs or hard wired.

The old one was on a 10ft pole - the new one a less rattly 6ft...

Needless to say i get all eight Freeview Multiplex’s perfectly, almost £200 down... oh well.

Patrick
North Worcestershire, UK

Hi Patrick. That's a nice looking log periodic.

Since this is mainly a left-pondian forum the subject of aerial connectors may need a bit of explaining. Most of the world including the USA has used F connectors for aerials for many years. It's really only the UK that has kept the traditional Belling-Lee co-ax connector. To a lesser extent it's used in the rest of Europe.
https://en.wikipedia.org/wiki/Belling-Lee_connector

The F connector is a much better connector. Better screening, better return loss. Easier to wire too. Though you do need the correct size conenctor for the cable and the simple versions only work with solid core co-ax.

The UK traditional aerial plug and socket is actually used in the vast majority of countries around the world on TV sets - its often called a PAL connector, but was also used in SECAM countries. The main exceptions to this rule is ex NTSC and North/South American countries where they use the F-Connector.

France actually had a similar slightly smaller plug on their early TVs but changed to the Bulgin Lee type, I suspect in the seventies. The Germans had a special two pin plug. Some Japanese portable sets, had either screw connectors or 3.5mm pin socket similar to a headphone socket today.

Over the years I have looked on the net at the aerial connectors on TVs all over the place, most countries in the fifties, sixties and early seventies used 300ohm flat cables with screw connectors, then converted. We had a 1955 Philips 405 line TV which had a UK Coaxial standard aerial socket, so I think the British may have been forerunners in using coaxial aerial cables on TV sets. Coaxial Cable of course helps prevent break in interference.

As you say, the F-Connector is more secure and better suited for satellite and aerial cables with a copper core and copper braid/sheath along its length. My first device with an F-connector, here in the UK was a Sony ST-3950 Stereo Tuner, I bought it in 1979, a beautiful device. It was supplied with a plug that required a crimp tool to fit. F-Connectors were of course used from the late eighties in Europe on Satellite TV, so F-Connectors are everywhere now, but TV sets outside ex-NTSC countries still use the UK type plug.

The antenna on the left looks like a shorter version of the Antennas Direct XG-91. I own one and it is not a rugged unit at all, having a mixture of aluminum and ferrous components plus snap-in plastic stuff but it works about as good as my other Yagi UHF antennas on band IV.

The antenna on the right looks exactly like a Blonder Tongue design:thmbsp:, which is an expensive one in the US due it's commercial-duty market. I have yet to find or try one of them. Since the US has retained all the previous VHF and only the UHF channels 14-36, former UHF designs (ch. 14-69) could all use some tweaks now.

The US has many areas that are extremely difficult to cover with UHF, VHF was retained because it is less affected by trees, hills, etc.

The one on the left, lasted me about 25 years (mine didn't have much plastic) but was attached to a high chimney and used to rattle. If it hadn’t been for the cable I think it would probably still work now. The aerial fitter disuaded me from having one of the fan type (like below) UHF arrays for the reason you mention, they tend to fall apart.

I will never understand why the UK didnt re-use VHF for TV after 405 line was switched off in 1985. I think we must have been the only country in the world to have TVs with UHF only tuners. Simple for tuning of course, but it meant portable TVs rarely worked properly without a rooftop aerial. Kinda missing the point, even so Casio sold loads of portable handhelds in the UK, just look on the ‘bay.

Of course we now have DVB-T and T2 digital TV which means most folk can receive 70 odd channels, not the previous 5. Plus free to air satellite with even more and we have the internet for portable devices..

The vast majority of TV's sold in Britain after 1970 were only fitted with a UHF tuner, I'm presuming that we were the only country in the world that did this. You'd see the odd one with a VHF tuner, I'm presuming that this was so they could be sold in Ireland or other system I countries that used VHF...

In Spain they where also U.H.F. only.

When UHF became de facto normal here in UK there were lots of areas that had poor reception compared to VHF, so they built many relay stations: These would usually be on a hill or high ground & receive a signal from a main station & re-transmit it on another channel, usually with vertical polarisation to reduce co-channel interference. In some mountainous areas they'd have relay stations relaying another relay station. There were a few places where they'd have a daisy chain of relay stations relaying one after another, what/where the longest daisy chain was I don't know...

Circular polarization is supposed to overcome those obstacles. CP came out in the 80's here. Many stations adopted it. It required the addition of a second transmitter. So those stations had double ERP.
https://www.tvtechnology.com/opinion...r-polarization

I am pretty sure everyone has seen the film Fahrenheit 451.

https://en.wikipedia.org/wiki/Fahrenheit_451_(1966_film)

During the opening credits that are spoken, images of UHF and a few VHF antennas are seen...

I don't know how things work on that side of the pond but UHF will never measure up to VHF for the raw coverage and penetration in the real world. I'm small town USA and ever since we went DTV and the b'cast went UHF it's been a challenge for reception. We have a few sub-channels running on ch-9 (186 MHz) that I can pick up with my amateur 2M Ringo but UHF is a little difficult despite their sub-megawatt ERP and 1470 AGL towers.
I applaud the forward thinking engineers who developed the PAL standard and 625 line system as it is far superior to our NTSC in many ways however I've always questioned the wisdom behind going exclusive UHF.

All 4 networks (BBC1, BBC2, ITV & Channel 4) were transmitted from every UHF transmitter AFAIK. This meant you only needed one antenna, usually pointed at the TX nearest to you. My nearest TX is the low power Nottingham relay & I can see it from my garage roof & gives a good signal, but, my antenna is pointed at Waltham a high power TX about 30 odd miles away, I used to be on Nottingham TX but nearly every time it thunders it goes off air for hours because of nearby lightning strikes, when Waltham has a lightning strike it goes off for about ten seconds then comes back on again, presume in has extra protection because it's a main high power TX...

Maybe so but what I do remember of the four was they were all about the same in terms of dry stuffy programming. Sorry but it wasn't anything I'd spend any time watching and that blinky 25 frames/sec made my eyes feel like two holes in the sand.

ARC Tech-109...After spending some time in Miami watching 60 Hz tv pictures the first thing I noticed when watching 50 Hz TV back in England was the flicker. Nowadays we have scores of channels on terrestrial digital antenna TV & I still can't find much to watch, my favourite channel is PBS America, & PBS channel 2 was my favourite channel when I was in Miami...

I remember when I started in TV we had a Saturday afternoon program about 2 guys fishing in a little boat on a river. I remember thinking why would anybody watch this crap. The answer is there was nothing else any better to watch.
Being off the air for only 10 secs is good. After we installed our back-up generator at the transmitter site, we were thrilled it only took about 7 secs. for automatic switchover. It was exciting working for a corporate engineer whose philosophy was "we were going to stay on the air no matter what just short of a direct nuclear strike."

That would have been the best 10 seconds for UK television. The what I remember was during the early 90's and it didn't take me long to find the power button.

When I goes to where I live now (2011), in the triple border with Brazil, Argentina and Paraguay, the TV stations are transmitting in analog mode yet. The Argentinian ones and some Paraguayan are 50Hz, because in these countries the power lines are 50Hz. In Brazil is 60Hz as in the USA (hence the PAL-M). I instantly noticed the flicker from 50Hz stations. 60Hz (in 480i) also produces some flicker but is less annoying.

CRT monitors capable of higher V scan ratios and hence resolution, you can apply 75, 85, 100 or even 120Hz (I have one that supports it but only at 1024x768, and supports 1600x1200 at 85Hz) and then not notice any flicker.

Flicker is worse when the screen occupies a greater fraction of your vision. This is simply because peripheral vision is more sensitive to movement (and hence flicker) than central vision. 60Hz may look OK when watching TV from a reasonable distance but it's horrible when close up to a computer monitor.

For interlaced pictures there is an additional 25Hz or 30Hz flicker which is hard to describe but very obvious on 625 or 525.

When I was a kid, the 50Hz large area flicker and 25Hz interlace flicker didn't bother me at all. That's how it was and most of us in Europe were used to it. In my late 20s (c1985) I got a job where I was investigating flicker on displays so I had to train myself to see it. Ordinary TV looked flickery then. We had an experimental rig that could show pictures with various scan rates and 2:1 or 1:1 interlace. 50Hz without interlace was pleasant. 100Hz interlaced wasn't too bad but 100Hz without interlace was lovely. It was also at the limit of the kit we were using so picture quality suffered in other ways. When I left that job I gradually became less sensitive to flicker again.

At the Broadcast Engineering Museum we have built an all-CRT gallery (control room in US parlance) so many of the monitors are inevitably in peripheral vision. They flicker horribly.

Very interesting your experience with it.

Funny... in the past, tech people worried about quality of movement/displacement of objects on display and choose/set 2ms or near it for CRT phosphours formula persistence. Times flies, and S/H (sample and hold) displays such as LCD and all variants (CCFL-backed, LED-backed etc) come in. The market flooded with these marvels but it seems only I are worrying about the horrible motion rendering of it (but all people loved the absence of flicker). No manufacturer are at least concerned with it at least in the beginning. Then: https://blurbusters.com/blur-busters...mple-and-hold/ I discovered that I'm not alone: the nature of these displays really havocs the manner that we perceive motion (blur), and then makers have spent some years in pursuit of things for mitigation it (such as flickering the back light). I prefer flicker. Less processing power needed for same motion perception (1000Hz capable video board? $$$$$). But is a headache for eg. typing a text for the Videokarma... this is the field where LCD reigns supreme due to S/H mode of working (and the individual addressable pixels).

Just in case, I don't believe we see with a 1000Hz frame rate biologically speaking, but I imagine that the motion/scan rate interacting with our own "scan" (variable for the peripheral vision, as you said), so the 1000Hz is for nulling any interaction. Proof of it is the difficult to see ficker on an 120Hz CRT. Besides other motion issues as explained in the link.

LATE EDIT: I'm maintaining some CRT monitors and the test UFO is very clear against regular LCD displays. Amazing to see. No blur in the UFO! Is possible to see it with full detail at scrolling, even at 60Hz frame rate. The CRT holds up. Only OLED with flickering can truly enters into this territory.

EDIT 2: I have a LG OLED TV that strobes the entire display once. Is horrible. Is usable only with 120Hz sources. Is different than a CRT monitor, due to the manner that CRT flickers (following the scan, not entire display once), even close watching the CRT monitor and hence seeing with some peripheral vision. Is good to save some dinosaurs to see the "real" new tech and what are really capable.

Naturally, for very slow movements, the S/H displays will not show artifacts.

Conclusion is the big size of newer TV's imposes automatically the nned of consider the peripheral vision and a eye-friendly reduction of blur.