UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Specific Vintage Equipment > Vintage Television and Video

Notices

Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc.

Closed Thread
 
Thread Tools
Old 15th May 2018, 10:23 am   #41
dave walsh
Dekatron
 
Join Date: Jan 2006
Location: Ramsbottom (Nr Bury) Lancs or Bexhill (Nr Hastings) Sussex.
Posts: 5,814
Default Re: TV system differences?

Blimey Synchrodyne, I thought you were going to say "so I shall be brief" but you have indeed taken a different approach and I found your antipodean overview very interesting indeed, especially the comments about transfer quality [Granada TV was my Region at the time-they were very innovative]. It will be nice to hear what the OP has to say from his part of the world, what he was after in the first place and how the Redifussion system came into being in his location?

Re Brigham's comment [at p40*] I've mentioned elsewhere, the BBC [1966?] viewer trial, reported in Wireless World, when the Beeb compared 405/625 images for the government. They said that 625 lines came out better. I didn't read it then but even I can see it's inaccurate. Most audience members reported little difference but the experts said otherwise. There may well have been political forces at work though, in terms of a possible European 625 line market.
Dave.

Last edited by dave walsh; 15th May 2018 at 10:42 am.
dave walsh is offline  
Old 15th May 2018, 11:18 am   #42
kan_turk
Hexode
 
kan_turk's Avatar
 
Join Date: Mar 2014
Location: Dublin, Ireland
Posts: 396
Default Re: TV system differences?

In fact both 525/60 and 625/50 live on into the digital era - SD services in the respective territories continue to use them

J
kan_turk is offline  
Old 15th May 2018, 6:08 pm   #43
emeritus
Dekatron
 
Join Date: Jan 2012
Location: Brentwood, Essex, UK.
Posts: 5,316
Default Re: TV system differences?

Domestic TVs were not capable of displaying 625 line analogue transmissions at their full resolution. I remember reading an editorial in "Wireless World " in the early 1990's titled something like "Who needs HDTV?" pointed out that the crt's of consumer TVs were only capable of displaying about half of the horizontal line information of a 625 line broadcast, the exception being some JVC models that had a 50% finer colour stripe width. Mention was made of a BBC demonstration of HDTV to some of their executives where one had commented on the picture quality, and that that this was the way of the future, only to be told that the demo hadn't started and he was actually watching a properly set-up 625 line studio monitor. Apparently this was one reason why people were satisfied with VHS VCRs that only recorded half the horizontal information: on the typical TV you couldn' tell the difference between live and recording. The only time I could see any difference between live, VHS, and SVHS was when I borrowed a video projector from work and tried it out at home on my matt cine projector screen (3' x 4', giving a 60" diagonal), using the S- video outputs of the TV and SVHS recorders. With this size of picture, the differences could be seen.

Last edited by emeritus; 15th May 2018 at 6:14 pm.
emeritus is offline  
Old 16th May 2018, 1:36 pm   #44
Richard_FM
Octode
 
Richard_FM's Avatar
 
Join Date: Sep 2017
Location: Stockport, Cheshire, UK.
Posts: 1,999
Default Re: TV system differences?

In the early 1990s there were a few analogue HDTV systems trials, IIRC one was 1250 lines that was backwards compatible with 625 lines SD.

This reminds me of when I bought a tubed Philips 21" TV in 2001 along with a Pace On Digital box. My Dad was impressed with the picture quality, thinking it was a digital signal when in fact it was just the analogue!
Richard_FM is offline  
Old 16th May 2018, 2:28 pm   #45
winston_1
Hexode
 
Join Date: Oct 2012
Location: London, UK.
Posts: 497
Default

Quote:
Originally Posted by kan_turk View Post
Quote:
Originally Posted by winston_1 View Post
Sadly that was usually the case. Problem was some areas had cabled systems with 625 at VHF (Stevenage was one), and blocks of flats were often like this as well. I had an argument with Philips over this when I wanted a set for such a situation. Didn't help though and I had to source a set from a continental manufacturer. Towards the end of the analogue era manufacturers, including Philips, started fitting all band tuners and still do to this day (except Panasonic).
Very interesting, and very strange given that Philips were marketing standard all-band and VHF/UHF equipped sets in Ireland from the 60s onwards - what era are we talking about?

Rgds
John
1980s.
winston_1 is offline  
Old 16th May 2018, 4:04 pm   #46
kan_turk
Hexode
 
kan_turk's Avatar
 
Join Date: Mar 2014
Location: Dublin, Ireland
Posts: 396
Default Re: TV system differences?

Quote:
Originally Posted by Richard_FM View Post
In the early 1990s there were a few analogue HDTV systems trials, IIRC one was 1250 lines that was backwards compatible with 625 lines SD.

This reminds me of when I bought a tubed Philips 21" TV in 2001 along with a Pace On Digital box. My Dad was impressed with the picture quality, thinking it was a digital signal when in fact it was just the analogue!
Your recollection is spot on - the 1250 line analogue system is near enough identical resolution wise to current 1080i digital - the only downside being the bandwidth occupied

J
kan_turk is offline  
Old 16th May 2018, 6:19 pm   #47
peter_scott
Dekatron
 
peter_scott's Avatar
 
Join Date: May 2003
Location: Edinburgh, UK.
Posts: 3,273
Default Re: TV system differences?

Today's HD standards are excellent but for someone born in the age of 12" screens and who now have far from excellent eyesight there really isn't much difference between 405 lines and 240 lines except for the very significant issue of flicker which I think was never acceptable.

My normal television is a 32" LED thing and I can't really tell the difference between 625 and full 1080 HD unless I get up close.

Peter
peter_scott is offline  
Old 16th May 2018, 6:34 pm   #48
Richard_FM
Octode
 
Richard_FM's Avatar
 
Join Date: Sep 2017
Location: Stockport, Cheshire, UK.
Posts: 1,999
Default Re: TV system differences?

I did wonder if any dual standard 625 / 819 line sets were made for the French market.
Richard_FM is offline  
Old 16th May 2018, 6:44 pm   #49
Brigham
Octode
 
Join Date: Mar 2006
Location: Co. Durham, UK.
Posts: 1,111
Default Re: TV system differences?

Only dual-standard sets were permitted to be imported into France for AGES.
It was often seen as an industry protection measure.
Brigham is offline  
Old 16th May 2018, 7:23 pm   #50
Cobaltblue
Moderator
 
Cobaltblue's Avatar
 
Join Date: Dec 2010
Location: Exeter, Devon and Poole, Dorset UK.
Posts: 6,822
Default Re: TV system differences?

Lots of great posts but the original OP has not come back and his last activity is 13th May when he posted the enquiry.

Cheers

Mike T
__________________
Invisible airwaves crackle with life or at least they used to
Mike T BVWS member.
www.cossor.co.uk

Last edited by Cobaltblue; 16th May 2018 at 7:42 pm.
Cobaltblue is online now  
Old 16th May 2018, 7:44 pm   #51
peter_scott
Dekatron
 
peter_scott's Avatar
 
Join Date: May 2003
Location: Edinburgh, UK.
Posts: 3,273
Default Re: TV system differences?

Does that matter?

Peter
peter_scott is offline  
Old 16th May 2018, 7:50 pm   #52
dave walsh
Dekatron
 
Join Date: Jan 2006
Location: Ramsbottom (Nr Bury) Lancs or Bexhill (Nr Hastings) Sussex.
Posts: 5,814
Default Re: TV system differences?

I wasn't ever hopeful Mike-three initial posts and no follow up so far. It's not uncommon but we never get an explanation There is a strong cross reference with the current thread in Forum Announcements "Members Last Activity". I think it would help if we weren't quite so helpful, looked at the history and waited for a response initially [especially on some of the repair enquiries] but not everyone agrees. This is a more [very] general topic so [ironically perhaps] it has inadvertently promoted a very interesting thread anyway, as it doesn't rely on OP participation to progress.

Dave

Crossed posts!
You are right that it doesn't matter in this particular case Peter, for the reason I gave there but it can be very frustrating in other situations you know. Beyond that the simplest overall answer to your question would be that this is a Forum!

Going right back to David's comment about the UK Dual Standard System [post 20*] from this distance it looks like a bit of a dog's breakfast, although interesting in terms of the adaptations that took place at the time. Post War "make do and mend" perhaps! As the main benefit of receiving on 625 lines was to gain BBC2, a lot of detractors couldn't see the point of all the silly intellectualism [Jazz 625, Hendrix and Ringo Starr turning up in the middle of Late Night Line Up etc] and stuck to 405 for as long as they could. There was a similar attitude in 1982 when Ch4 debuted.

Last edited by dave walsh; 16th May 2018 at 8:09 pm.
dave walsh is offline  
Old 16th May 2018, 8:21 pm   #53
emeritus
Dekatron
 
Join Date: Jan 2012
Location: Brentwood, Essex, UK.
Posts: 5,316
Default Re: TV system differences?

If it wasn't for BBC2 there would probably have been no "Tonight in Person" programmes like the hour-long one featuring Peter, Paul and Mary that has probably had more views of its YouTube incarnation than it had for its original airing.

I have a Schneider 625 line VHF/UHF colour TV inherited from a relative who lived in France, that works with SECAM, European PAL, and UK PAL. I assume the UK PAL capability was for the benefit of those in range of the Channel Islands transmitters.
emeritus is offline  
Old 16th May 2018, 9:12 pm   #54
Richard_FM
Octode
 
Richard_FM's Avatar
 
Join Date: Sep 2017
Location: Stockport, Cheshire, UK.
Posts: 1,999
Default Re: TV system differences?

Quote:
Originally Posted by Brigham View Post
Only dual-standard sets were permitted to be imported into France for AGES.
It was often seen as an industry protection measure.
It crossed my mind that the French developed SECAM as a form of protectionism, rather than use PAL, though it was a little easier to convert for international live events.
Richard_FM is offline  
Old 16th May 2018, 9:39 pm   #55
Croozer
Pentode
 
Join Date: Jul 2016
Location: Edinburgh, Scotland, UK.
Posts: 110
Default Re: TV system differences?

What an interesting thread!
The one issue that surprises me is how long the 405 network persisted after 625 had been established. Presumably single standard 405 TV's stopped being produced in the mid sixties, but did new dual standard TV's go on beyond 1969 when BBC1 and ITV migrated and went colour?
I seem to remember the 405 channels being treated as the 'core' network by the broadcasters right up to the end - Eg. childrens TV was displaced to BBC2 on budget day so that BBC1 could carry political coverage.

Maybe the robustness of VHF transmission in comparison with the new broadcasts?

The digital switchover was far harsher.
Croozer is offline  
Old 16th May 2018, 10:11 pm   #56
peter_scott
Dekatron
 
peter_scott's Avatar
 
Join Date: May 2003
Location: Edinburgh, UK.
Posts: 3,273
Default Re: TV system differences?

Yes, apart from a little gap to fight the Nazis 405 ran from 1936 through to 1984. A real testament to the remarkable vision of its developers.

Peter
peter_scott is offline  
Old 16th May 2018, 10:22 pm   #57
Radio Wrangler
Moderator
 
Radio Wrangler's Avatar
 
Join Date: Mar 2012
Location: Fife, Scotland, UK.
Posts: 22,797
Default Re: TV system differences?

Standards conversion and SECAM was a bit of a joke.

It turned out that SECAM was the very devil to mix and do the usual video tricks to because of the delays needed. So programmes were made in PAL and only at the last stage converted to SECAM for transmission.

Supreme Effort indeed!

David
__________________
Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done
Radio Wrangler is offline  
Old 16th May 2018, 11:34 pm   #58
dave walsh
Dekatron
 
Join Date: Jan 2006
Location: Ramsbottom (Nr Bury) Lancs or Bexhill (Nr Hastings) Sussex.
Posts: 5,814
Default Re: TV system differences?

On reflection, I think that BBC trial I mentioned, may have been about colour on 405 lines [which I do agree was a very durable b+w standard]. You only have to look at the [properly set up] 405 line sets Mike Barker exhibits regularly at Golborne to see how really very good it can be. The erudite comments about loss of definition when a larger screen is used [ie beyond the regular CRT sizes] perhaps go a long way towards answering my frequent question-Why didn't we just go ahead into colour with 405? On the other hand, apart from the international compatibility issue, there would have been no real concept of what future screen sizes might be, at the time, despite Baird's work back in the thirties.

Dave W

Last edited by dave walsh; 16th May 2018 at 11:42 pm.
dave walsh is offline  
Old 17th May 2018, 12:32 am   #59
Synchrodyne
Nonode
 
Join Date: Jan 2009
Location: Papamoa Beach, Bay of Plenty, New Zealand
Posts: 2,943
Default Re: TV system differences?

Quote:
Originally Posted by Richard_FM View Post
I did wonder if any dual standard 625 / 819 line sets were made for the French market.
Yes. Apparently that was the normal form for French TV receivers when the 625-line UHF service was introduced in the early 1960s. I’d guess that it was maintained until the 819-line service was duplicated on 625.

Click image for larger version

Name:	WW 196111 p.560 French Dual-Standard TV.jpg
Views:	61
Size:	79.2 KB
ID:	163034

Before then, there were multistandard French TV receivers for the border areas. These generally followed the Belgian precedent, and could receive 625 Systems B and C and 819 Systems E and F, usually with limited channel coverage for System E. There were also one or two that could receive 405 System A in addition to the others listed. When UHF arrived, System L capability was added to the Belgian and French multistandard receivers.

Click image for larger version

Name:	WW 195406 p.263 French Border Area TV.jpg
Views:	74
Size:	86.6 KB
ID:	163035 Click image for larger version

Name:	WW 195910 p.456 French Multistandard TV.jpg
Views:	71
Size:	93.0 KB
ID:	163036 Click image for larger version

Name:	WW 196510 p.501 French Border Area TV.jpg
Views:	62
Size:	82.4 KB
ID:	163037

The French setmakers were thus accustomed to the 625 and 819 combination before it became the norm. The French System L 625-line key parameters of positive modulation and AM sound (without pre-emphasis) were chosen to align with those of System E in order to make easier the design (and cheaper the manufacture) of dual-standard receivers. That choice has sometimes been described as a protectionist measure – perhaps it was, although nowhere have I seen any hard supporting evidence for the assertion - but it also had a good engineering rationale. For the Outré Mer territories, where there was not the precedent of System E transmissions and so no need to consider dual-standard receivers, the French used System K’, which was of the negative/FM type. That fact I think somewhat weakens the protectionist argument, but strengthens the engineering case for the System L choices.

Also in respect of helping dual-standard receiver simplicity, the System L standard IF (32.7 MHz VIF, 39.2 MHz SIF) was chosen to align the sound carrier with that of the System E standard IF (28.05 MHz VIF, 39.2 MHz SIF).


Cheers,
Synchrodyne is offline  
Old 17th May 2018, 12:34 am   #60
Synchrodyne
Nonode
 
Join Date: Jan 2009
Location: Papamoa Beach, Bay of Plenty, New Zealand
Posts: 2,943
Default Re: TV system differences?

Evidently French dual-standard receivers go back to the early years – according to this Wireless World item, there were some 441/819-line examples.

Click image for larger version

Name:	WW 195111 p.459 French Dual-Standard TV.jpg
Views:	62
Size:	70.0 KB
ID:	163038

And there were 405/819-line receivers for those viewers who were in range of the Channel Islands transmitters:

Click image for larger version

Name:	WW 196210 p.482 French 819-405 TV Receivers.jpg
Views:	63
Size:	90.8 KB
ID:	163039

The French were also early with bilingual sound transmission, in 1957 in Algeria:

Click image for larger version

Name:	RE 195708 p.52 Bilingual TV.jpg
Views:	60
Size:	76.1 KB
ID:	163040


Cheers,
Synchrodyne is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 9:11 am.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.