Low band TV in Britain.

[marcel]

Long before PAL Brittan and parts of europe were experimenting with color after NTSC came into existence. I could see a large tube and set OEM like philips making their own color CRTs on an experimental basis. Philips actually produced a roundy color for both Canada NTSC and european PAL markets, but I believe it used a 21FJP22....It would be interesting to know if they made their own CRT or bought American


I have two Philips TVs with a round color picture tube.
The Philips 21KX100A has a RCA 21FBP22.
The Philips EL-5793 has no numbers on the picture tube. This has a brown connection to the picture tube. According to Philips an AX53-14. I don't know if Philips made this picture tube itself, but someone might recognize this picture tube.


Also two photos of a new RCA 21FBP22, bought in the Netherlands.

The Philips EL5793 http://www.marcelstvmuseum.com/photoalbum85.html
The Philips 21KX100A http://www.marcelstvmuseum.com/photoalbum30.html

[NewVista]

Originally Posted by Colly0410

..Channel 4 from Meldrum for North east Scotland ...

As long as you didn't have to watch Molly Meldrum on station at Meldrum

[wa2ise]

Heard an urban legend that said that the BBC had to continue broadcasting 405 lines because there was a grandmother that still had a working 405 line set and no 625 line set. I would have thought that the BBC would give her a 625 line set so that they could shut down the 405 line transmitter...

[Colly0410]

When France shut their 441 lines system down anyone who had a 441 lines only TV were given an 819 lines TV as it was cheaper than keeping the 441 system running. Why the BBC & ITV didn't do this I don't know... There were very few people using 405 lines only TV's when it was shut down completely in Jan 1985, vast majority of folks had gone over to 625 lines colour by then. Someone gave me a 405 only TV in 1981, it worked for a bit then started smoking so turned off quick, took it outside & plugged it into an extension lead, it then smoked a lot & went "PHUT" & it died & that was that. Never saw another 405 lines picture again..

[ppppenguin]

BBC and ITV continued with 405 past any reasonable date for switching them off. Switched off at start of 1985, duplication of services on 625 started in 1969, It would have been cheaper to switch them off some years earlier (perhaps 1980 or so) and give anyone legitimately still watching on 405 a new set.

I don't know the politics of the timing of the 405 switch off. "Granny watching on 405" was surely urban myth. By comparison the digital switchover was done from 2008 to 2013 though DTV had been transmitted as early as 1998. Set top boxes were given free to certain vulnerable and elderly people.

[Colly0410]

A single low band transmitter covered almost all of northern England, it was Holme Moss channel 2 TX'ing at 100 KW's high up in the Penines, it's signal reached both the north & Irish sea coasts, North Wales & the Eastern coast of Ireland. It's now an FM only TX now but still travels, I can receive BBC radio 2 on 89.3 here in my home near Nottingham & received it in Blackpool last week so it still travels far...

[Colly0410]

A big problem with low band here was co-channel interference: In summer reception would often be ruined by patterning &/or distorted sound. It'd usually be 625 line TV stations from the European mainland coming in via sporadic E, most of these used negative video modulation & FM sound, the 405 British system used positive modulation & AM sound (Belgium used positive modulation & AM sound for their 625 lines system) & a 405 set couldn't resolve a 625 transmission properly. Received French 819 lines TV a few times with a split picture on UK channel 3, there was no sound though...

[Telecolor 3007]

That "Philips" 21KX100A is something that I wish me.

[Electronic M]

Originally Posted by Telecolor 3007

That "Philips" 21KX100A is something that I wish me.

Same here. I understand they made an NTSC version for the Canadian market... I've never been to Canada before but I would make the trip for one.

[marcel]

The 21KX100A's in the Netherlands are original NTSC, later converted to PAL, PAL modules were made for it. These TVs are also very rare here in the Netherlands. I've never seen a picture from Canada with this 21KX100A. Maybe a member in Canada knows if these TVs were sold there, maybe under a different model number.

On the photo my 21KX100A in my living room together with an EL3400 video recorder from 1964, is black en white. Picture on tv from DVD player.

[Telecolor 3007]

I've seen pictures with that V.T.R., but didn't imagine it was that huge!

[Colly0410]

Another problem with low band TV here in England was car/motor bike ignition interference, because it used positive video modulation & AM sound any interference pulses caused white flashes on the screen & pops & crackles in the sound, this could be quite annoying.... One sunny Sunday afternoon I'd replaced the chain on my Honda 50 motor bike & was riding it up & down the road to bed the chain in & get the tension right. An irate lady came out of her house saying I'd ruined her Sunday afternoon viewing with my interference - oops, I then went on country roads to bed the chain in...

[Telecolor 3007]

While I was looking for something else, I found this: https://www.transdiffusion.org/2017/...to-625-line-tv
If you people do have time, take a look. From a historically point of view, it's very intresting.
Anyway, did any private tv station broadcasted in V.H.F. band in Great Britain?

[Colly0410]

All the ITV companies transmitted on VHF high band/band3, only the BBC ever transmitted on the 5 low band/band1 channels..

[Colly0410]

I've often wondered why ITV didn't use low band/band 1? I'm thinking the London area could have used channel 5 & the north of England reused channel 1 as used by BBC in London as was far enough away from London to avoid co-channel interference. The gap between channels 1 & 2 was quite big because the original channel 1 from Alexandria Palace was double sideband so would have hopefully avoided adjacent channel interference. I suspect the real reason is the BBC took the hump & blocked ITV from using low band/band 1 for political purposes...