RTE One in 405 lines in 2011

rlogue

Unbelieveable as it may seem, you can still get RTE One on Channel 7 in 405 lines in some places in 2011.

Here is a clip from tonight's Prime Time as picked up on my 1969 Sony dual standard portable TV...

Very nice! Have never seen a 405 broadcast in the flesh but that's very impressive.

rlogue

I grew up with RTE on channel 7 in the early 70s and it wasn't a bad picture at all.

Obviously the smaller the screen the better the picture but I have been getting excellent results on my little Sony that has just had the 405 section nicely restored.

If anyone wants to know how its all done, just ask...

Galway

rlogue wrote: »

I grew up with RTE on channel 7 in the early 70s and it wasn't a bad picture at all.

Obviously the smaller the screen the better the picture but I have been getting excellent results on my little Sony that has just had the 405 section nicely restored.

If anyone wants to know how its all done, just ask...

Please tell us!

rlogue

Now obviously there aren't any over the air 405 line transmissions anymore, but there are standards converters out there.

The converter I use is an Aurora Converter which is available over the Internet at http://www.tech-retro.com/Aurora_Design/Home.html

There are different converters available for different standards like the old French 819 line and 441 line standards and these take a standard video signal and turn it into a suitable signal for a vintage TV.

My Aurora can be tuned to any of the old 405 line VHF channels 1-13. I've tuned mine to channel 7!

Next up you need a video source. Normally I use a cheapo Freeview box beside the Sony TV but on this occasion I used the live feed of Prime Time on the RTE website - converting a laptop's VGA output with a PC to TV converter and feeding that in turn to the Aurora and then from the Aurora to my Sony.

So there you are - RTE 405 lines is alive and well on Channel 7 in London!

watty

Isn't there going to be 405 Transmission from Alexandra Palace or nearby this year in 405 lines and VHF band I?

Mike 1972

All good and ready for the digital switchover

rlogue wrote: »

Unbelieveable as it may seem, you can still get RTE One on Channel 7 in 405 lines in some places in 2011.

Now all you need is 405 line colour

watty

/me shudders.

It was stupidity that after WWII the TV was restarted on 405 lines (about 378 visible). Not that many TVs and many of them only Band I. 625 lines was tested in 1945 and public transmissions in 1948.

405 Colour might have locked Britain and likely Ireland to 405 lines until the rollout of Digital or maybe Analogue Satellite!

US is stuck on 525 lines (480 visbile ) since before WWII (tests) because of early fifties addition of color. Only with Digital HD 720p and HD 1080i do they have an improvement.

405 lines is excellent maybe up to 15" or 17" set. It looks poor on 26" On a 21" set you notice a big difference between 405 lines and 625. I fixed enough of them to remember!

Mike 1972

watty wrote: »

It was stupidity that after WWII the TV was restarted on 405 lines (about 378 visible). Not that many TVs and many of them only Band I. 625 lines was tested in 1945 and public transmissions in 1948.

Inclined to agree. Think the Beeb missed a big trick not using 625 in 1946. Had they done so they would have had to use Bands 1 and 3 to get national coverage so that by the time ITV came along (mid-late fifties) they would have been forced to stick most of their transmitters up in the (at the time) largely untried and untested UHF band. Only real advantage of 405 was the narrow 5 MHz channel bandwidth (although 441 with negative polarity and FM sound could also have been squeezed in) Ive heard widely varying figures for the number of TV sets in the UK in 1945 (from a few hundred up to 20,000)

Mind you if one wants a long painful history of line standards look at France

Im kinda wondering what the OP has against 625 though. In one thread hes faffing about trying to revive RTE1 on 405 and in another hes complaing about not being able to watch RTE2 in 1125 (1080i) :pac:

watty

Nostalgia

Google gerry wells radio museum video

One question I always had about 405 was the sound quality, as it used AM for the audio would the sound quality have been similar to a MW or LW radio broadcast?

rlogue

Nope the sound quality was pretty good as the sound channel had plenty of bandwidth.

Mike as for you - please allow this old man to indulge in his double standards. Dont forget I campaign for legal access to Irish TV outside Ireland.

P.S. welcome to Eritrea. Now funk off!! ;-)

watty

10KHz I think.
Some TVs had separate sound IF, more expensive and better quality and allowed option of FM demodulator and BandII "biscuit" in tuner.. Intercarrier type Sound IF was prone to buzz and inherently would not work for Radio only.

I repaired quite a few 405 sets as a hobby between 1968 and 1973. The Dual standard ones by soldering in 625 position.

Interference from ignition is white specks on 405 and dark specs on 625 due to opposite sense of vision modulation. French SECAM 625 used Positive like 405 line.
http://en.wikipedia.org/wiki/405_lines

See also
http://www.irish-tv.com/405.asp

I've had too little money, not enough space and too many moves to different countries to keep nostalgic stuff I had accumulated in late 1960s and early 1970s starting as a Primary School kid with an portable valve Radio for Luxemburg 208 and WWII R1155 set for Short Wave. I had a Cossor scope dating from 1950s and one 405 set with corded remote and FM Radio on the tuner turret. Giant soleniod to push the turret round.

The valve tuners had a rotating turret / drum with brass studded "biscuits" clipped in at surface for each channel. These had the coils and capacitors for RF tuning and RF local oscillator. So unlike later push button tuners, each rotary position was a fixed channel.

PyeContinental

rlogue wrote: »

Unbelieveable as it may seem, you can still get RTE One on Channel 7 in 405 lines in some places in 2011.

But if your method is simply converting a modern 625 line or digital signal to 405 line and inputting that into your 405 line tv, then you can't get 405 lines in "some places" in 2011. You can either get it nowhere as it's not broadcast, or else you can get it everywhere, because anyone could use your method.

Sorry if I've taken you too literally, but I hate to feel that I've been cheated, and I was expecting to be very surpsrised to hear that there was some transmitter or relay somewhere which was still broadcasting in 405 lines.

I remember when the 405 line services was shut down in the early 80s. That was when the Pye Continental TV set which my father once watched the 1960 Rome Olympics and the 1969 moon landings on became obsolete.

It now displays a digital HD colour picture, but that's because I took the tube and valves out and put in integrated circuit boards and semi conductors. I'd say it's likely that wouldn't sit too well with some people here, but I did mull over the decision to do this for about a year, and I made sure I've kept all the parts and made no changes to it that can't be reversed.

watty

The OP was a bit tongue in cheek. He and I know where some real Band I 405 transmissions might take place, oddly the licence condition includes not publicising it. Why that is I can't imagine. I'm not in that Jurisdiction, nor is this web site.

It's true though that there are some pre 1939 sets still running and there are various ways to get a picture on them. Plenty of late 50s to early 1970s sets.
1) Reprogramming VGA timings and using VGA to composite adaptor (very simple) and Band I 405 standard Modulator (not hard to build on stripboard with one transistor as AM 3.5MHz sound subcarrier oscillator/Modulator and one transistor AM 50MHz approx oscillator/Modulator.
2) Off the shelf standards converter that takes regular 625 composite signal.
3) Modifying analogue camera with vidicon, plumbicon or orthicon tube to scan 405 line directly. Pretty easy on older ones that are all discrete. Some early 625 cameras are modified 405 line models!

Feed PC or standards converter with source of choice.

PyeContinental

watty wrote: »

The OP was a bit tongue in cheek. He and I know where some real Band I 405 transmissions might take place, oddly the licence condition includes not publicising it. Why that is I can't imagine. I'm not in that Jurisdiction, nor is this web site.

Of course I understand that the OP was being tongue-in-cheek. I still felt disappointed and "cheated" to read that this was only about converting a modern signal. I wouldn't have thought that this possibility was news to anyone on this forum. I expected a more intruiging reveal.

I would have got as much of a kick out of seeing that Sony TV, without the "cheat" because the most impressive thing to me about it is how modern it looks, and how ahead of its time the styling was. Compare that to a set by any other brand of the same vintage and it would look decades ahead. That tv set would have still looked contemporary in the 80s. I bet it would draw a few breaths to hear how much it cost back then and what percentage of the average yearly wage it would have cost.

I would be interested to hear more about who is still broadcasting in 405 lines and where.

rlogue

There aren't any 405 broadcasts yet but there will be in the South East of England at some point, which is why I went to the trouble of obtaining a 405 set.

The Sony does have a fairly contemporary design despite being 42 years old! It is a superb little set and produces an excellent picture.

The Sony is also my only CRT set. We have one LCD TV in the sitting room and all other TV watching is done via laptops with the help of the DVBViewer recording service.

PyeContinental

Why will 405 line broadcasting begin again?

How much did you pay for the tv? Did you have much competition for it? Is there much of an interest in retro tv sets would you say?

rlogue

To answer that question I say why not? There are many enthusiasts out there who have the know how to restore the old receivers and transmission equipment.

I paid 90p for the TV and a bit more than that to get it working again.

It's a very specialised hobby but I think it goes in hand with the trend for all things retro.

PyeContinental

Even if not working, and judged as a piece of antique furniture alone I would say 90p sounds like a great bargain. I would say it's the kind of thing that could generate a runaway bidding fenzy if the right people saw it and decided they wanted it.

Can you be less cryptic about the 405 line transmission topic? Who exactly is going to be broadcasting on 405 lines in the future, and specifically why?

rlogue

I have to be cryptic as I don't want to jeopardise the project, however I can suggest you Google British Heritage Television.

rlogue

By the way I'm fascinated by what you've done to your Pye Continental - any chance of some pictures of it I'n action?

watty

Retro Tech

http://www.vintage-radio.net/forum/index.php

Also google BAMA boat anchor

"you could use some of those old sets as a Boat Anchor!"

My friend Al is going to write more soon:
http://www.techtir.ie/node/1001693
Imported from Forum Software, so illustrations are not inline yet http://www.techtir.ie/node/1003266

PyeContinental

Thanks - I see there's a lot of reading to be done on both of those forums - I'll read through them later when I have a bit of time.

I haven't any completed photos of the Pye Continental, as it's still really an incomplete work in progress, and my objective changed a bit along the way, but I took some pics when I was disassembling it at least. I'll have a look for them now.

PyeContinental

Disassembing #1

PyeContinental

Disassembling #2

PyeContinental

Picture attachment called Pye15 was a "proof of concept" for myself, by putting the PC inside the chassis, and I also liked the juxtaposition of new inside old.

Since then, I removed all the parts from the PC and made a customised chassis for them, partly out of metal from the motherboard tray and plywood to complete a case which slides into the chassis of the Pye.

I have hard disks in a separate enclosure above the metal/wood case which houses the PSU, motherboard, cpu, memory and TV tuner cards.

The power switch goes to an arcade type button which fitted perfectly into where the power dial was on the left. I would like to fit USB ports into the same area, but the rule I made for myself was that there was to be no cutting or damaging of the original fascia or buttons.

The idea then was to fit an LCD panel in place of the tube, but since then I changed my mind, as I have the output going to a large LCD tv which sits on top of the Pye cabinet, and having a screen inside the cabinet seemed like unnecessary duplication.

My plan, when I have time, is to make it looks less Frankenstein-ish and to build a wood panel with USB ports and what not, and blu-ray drive, and a section for the HDDs so that they can be inserted and removed from their enclosure. I'm not very proud of how it looks in its current form, but it works well, and as a nice piece of furniture, I'm glad it still has a functional use in the 21st century.

Antenna

Mike 1972 wrote: »

Inclined to agree. Think the Beeb missed a big trick not using 625 in 1946. Had they done so they would have had to use Bands 1 and 3 to get national coverage so that by the time ITV came along (mid-late fifties) they would have been forced to stick most of their transmitters up in the (at the time) largely untried and untested UHF band. Only real advantage of 405 was the narrow 5 MHz channel bandwidth (although 441 with negative polarity and FM sound could also have been squeezed in)

monochrome '625line' TV could have used 5MHz RF channels too - though with a horizontal resolution about the same as that from monochrome VHS.

Mike 1972

Antenna wrote: »

monochrome '625line' TV could have used 5MHz RF channels too - though with a horizontal resolution about the same as that from monochrome VHS.

It could have but what would have been the point ?

One or two countries in South America have a system called PAL-N which uses American 6 MHz channels for carrying 625 line broadcasts. The Belgians (IIRC) also attempted 819 line broadcasts on 7 MHz (as opposed to 14 MHz) channels

Basically it amounts to trading off vertical resolution for horizontal resolution.

watty wrote: »

10KHz I think.
Some TVs had separate sound IF, more expensive and better quality and allowed option of FM demodulator and BandII "biscuit" in tuner.. Intercarrier type Sound IF was prone to buzz and inherently would not work for Radio only.

Prior to the advent of NICAM the sound quality on the overwhelming majority of TV sets was rubbish anyway regardless of what system was in use. The advent of stereo prompted (some) manufacturers to pay more attention to sound quality although one side effect of the move to flatscreen TV's is that the benefits of a large cabinet in terms of bass response have been lost.

Mike 1972

Mike 1972 wrote: »

The advent of stereo prompted (some) manufacturers to pay more attention to sound quality although one side effect of the move to flatscreen TV's is that the benefits of a large cabinet in terms of bass response have been lost.

That's certainly true. The sound from my 40" Samsung C530 is very flat compared to my 21" Sanyo CRT, so I fed a SCART output to a stereo system.

I also know of someone who chose a 768 line, MPEG-2 LCD specifically because it had proper speakers.

Stinicker

Crikey Sony were well ahead of the game back then having a remote control and all, when did remotes become more mainstream?

watty

1970s USA. Ultrasonic. Which is why most IR uses 38KHz carrier (Ultrasonic was 36KHz to 42KHz).
From 1950s to 1970s some TVs, even in UK, had cabled Remote controls.

My grandmother had a Luxor TV in the mid 80s with an IR remote but they were going around for a while before that; I once saw promo for Oracle from the 70s with it being displayed on a TV with a wired remote.

Tax The Farmers

Re: The wisdom Or otherwise of the Beeb using 405 in 1946 they probably didn't have much choice in the matter as there was little or no knowledge of the 625 line technology in the west in 1946. It was pioneered in the USSR and towards the end of the decade was taken up in Germany and subsequently the rest of Europe (the Dutch briefly experimented with 567 lines)

During the 1960's the BBC did toy for a while with the idea of 625 lines on 5 MHz VHF channels (alongside 8MHz channels on UHF in order to avoid having to replan the UK's VHF allocations. The idea was dropped -possibly to avoid the complexity of dual colour standards (The VHF system envisaged a chromince subcarrier frequency around 3.6 MHz).

I don't think you could really say there was "was little or no knowledge of the 625 line technology in the West in 1946."

405-line was quite literally the first fully electronic television system developed by Marconi and EMI in the UK.

Analogue monochrome television standards are all basically the same technology just in different configurations to squeeze more information into certain bandwidths.

There wasn’t a ton of difference between 625 and 405 on the small screen that were typically used in the UK in the 50s and 60s.

BBC ran colour tests with NTSC on 405 which worked fine and they tried SECAM. They eventually settled on PAL, largely because it was the preferred EBU standard. It didn’t make a ton of sense to be out on your own.

The 625 line standard just happened to be optimal - able to be squeezed into somewhere between 5 and 6 MHz

The choice of UHF for 625 PAL in the UK is completely arbitrary. VHF is generally easier and RTE and plenty of others broadcast PAL-625 on VHF for decades. Australia for example used DVB-T on VHF.

UHF is far more line of sight and less suited to rolling landscapes. The only significant advantage is it requires much smaller antennas, which is a significant thing in a country like the UK with a lot of over the air reception and roof antennas as it reduces clutter.

France adopted 819 lines for example, which was far too bandwidth intensive (14 MHz!) to combine with colour subcarriers, so was dropped when SECAM was introduced.

Also there were practical implications of having to make different types of tubes for different markets.

Here’s how it looks:

https://youtu.be/yB2HB_QhZfQ

TAFKAlawhec

Holy Thread Resurrection, Batman!

Anyway...

"The choice of UHF for 625 PAL in the UK is completely arbitrary. VHF is generally easier and RTE and plenty of others broadcast PAL-625 on VHF for decades. Australia for example used DVB-T on VHF."

The UK decision for having their 625 line analogue PAL service was that there simply wasn't the space in their VHF Bands I & III to carry such a service & maintain the two 405 line services already in place - when the 405 line nets were shut down for good in 1985 they could have done something similar to the French and replan the allocations similar to that used in the ROI, but they didn't preferring to reallocate the bands for PMR mostly (a missed opportunity IMO). In much of the rest of Europe, the VHF bands were simply the first ones used for broadcasting the first (usually public or state) channel and when space ran out for them, started using their UHF allocations. The ROI was a general exception to having two national TV networks largely carried on the VHF bands, most countries could only give space for one with a second channel having to start on UHF (with some odd exceptions e.g. the Santiago transmitter in Spain carrying TVE2 on Band I whereas it was on UHF elsewhere in Spain).

As it is, the majority of European countries that used to have 625 line analogue transmissions on VHF have DVB-T/T2 transmissions today only on UHF and have largely abandoned it - even the Italians that would fill every spare channel allocation going have largely abandoned it now if the details on digitalbitrate are accurate. Of the top of my head, only Finland, Poland and possibly Sweden maintain VHF DVB-T/T2 networks today. And while Australia still uses DVB-T on VHF Band III, it is somewhat ironic that this practice exists mostly in the major cities whereas the regional and rural areas are reliant on either UHF transmissions or the VAST satellite scheme (the reasons are down to maintaining general antenna compatibility with prior analogue broadcasts). Interestingly, New Zealand did not retain their VHF bands for DVB-T broadcasting and have reallocated them for other non-broadcasting uses IIRC.

"France adopted 819 lines for example, which was far too bandwidth intensive (14 MHz!) to combine with colour subcarriers, so was dropped when SECAM was introduced."

The French, including the famed Henri de France, did tests using SECAM on their 819 line transmission network and could have ran an 819 line SECAM colour network if they wanted to, the same way the UK could have run a similar one for 405 lines on either PAL, SECAM or NTSC - however as the French authorities had agreed in the early 1960's (around the time of the Stockholm Frequency Conference in 1961 IIRC) to adopt 625 line transmissions/recordings for better compatibility with programme exchange across the EBU & elsewhere in Europe, and thus decided that the adoption of SECAM colour would be restricted to 625 line transmissions for the public and that the TF1 network would itself become a UHF 625 line service after a simulcast period (like BBC One & the ITV stations in the UK - indeed one of the main reasons for the UK adopting 625 line broadcasts as recommended by the Pilkington committee was for similar programme exchange reasons, as well as accepting that using 405 line transmissions on UHF would waste significant bandwidth as prior agreement had already been agreed for all of Europe to adopt a common 8MHz channel bandplan for 470-960 MHz TV transmissions at Stockholm 61 as opposed to the hotch potch of band plan allocations in the VHF Bands I & III that lay across Europe).

icdg

Yeah, we don’t drag up old threads. I don’t say this for fun, as I want to remind people, it’s because posters are very quick to attack old posts which are saying things that were true at the time without taking notice of the date stamp,