Great to see this video - thanks for posting it! I remember Gerald Wells and the museum - amazing that he manufactured his own valves in the workshop in his garden. From recollection, ITV Midlands (ATV and ABC) was broadcast on VHF channel 8 from the Lichfield transmitter, whilst BBC Midlands TV was on VHF channel 4 from Sutton Coldfield. I'm not sure why the two TV channels weren't co-sited.
Not really a difference between VHF and UHF, but rather a difference between PAL and NTSC(Designed by RCA). In the US, there were so many B/W TVs sold nationally by 1954(year of NTSC adoption) that anything in the way of color broadcasting that was not compatible with the existing standard would be all but rejected by the public and manufacturers, note the earlier FCC adoption of the incompatible CBS field sequential color system, CBS even with the government's grace couldn't get manufacturers to sign on. The British and Europe only started thinking about color a decade later. By the 1960s, the 405 line system was very dated, having been inferior all along to the US system, it didn't really make sense to build color on top of it like NTSC, and with the limited bandwidth allotted between channels, I'm not sure it was even possible. Since they were dropping the 405 line system all together, it only made sense to solve any remaining issues with NTSC and tailor it for the 50hz power frequency by having 625 lines at 25 times per second instead of 525 at 30 times per second, ignoring interlacing. The UK kept simultaneously broadcasting in 405 line for years after the PAL flip, kind of like what we did here with the digital transition. VHF and UHF are just frequency bands. The high pitch is the horizontal scanning rate of a 405 line set, (405 lines)*(25 frames per second)= 10.125kHz, the sound you are hearing. The higher pitch out of NTSC sets is 15.75kHz, it is just as loud, just that ones ears roll off the higher frequency.
What a fantastic video of a fantastic place, the televisions actually work and are switched on. It's looks like my bedroom in the 70's and 80's! I bet all those valves make that place warm. I see you had to use RUclips's image stabilization, so much to look at and so exciting you couldn't keep the camera steady Frank, haha! When conditions were right and with a motorised VHF Band III loft aerial I could receive ATV in Reigate, the signal had to come over the North Downs. No idea which transmitter it was from, I can't remember the channel number. The video brings back good memories for me but for one thing I'm glad to see the back of, the high pitch whistle (10.125KHz I believe), it's still ringing in my ears after watching the video!
the V W M . in Rosendale Road was a fantastic place. G W even had a machine for re-constructing and re-vacuuming valves in a subsidiary shed in the garden.
At an early age in the 60s, grandmother's house was the only place to watch tv. I was so fascinated by the lopt ringing, test cards and tv dxing. Some weather conditions enabled other far off regions of itv Stations to be received. Wonderful times and memories of the good old 405 turret channel changer. Sadly I have no interest in todays all singing and dancing smart tv's.
I love glass television sets, the rounder the better. Unfortunately in New Zealand where I am, the older sets are rare and nothing earlier than 1960 seems to be available, being the year transmission of the NZBC began its b&w service. Color didn't begin til 73 and I well remember going to the trades fair in Wellington to get my first glimpse of a color set. Magic.
@ShymFan2007 Because the (colour) TV techonology at the time was very expensive to implement and New Zealand had a relatively small population with a less prosperous economy than now..... the BBC spent a fortune switching over to colour in the late 1960s, and only the rich could afford the first colour TV sets in the UK, in fact many people rented black and white TV sets at the time
The waveform monitor is displaying two lines of picture information - line sync pulse followed by the colour burst superimposed on the back porch, then video information (luminance and chrominance together), ending with the front porch.The colour burst is a sample of the subcarrier oscillator from the source, which provides the phase and amplitude reference for the QAM modulated chrominance signal during the active line period. The phase of the chrominance signal determines the hue that is displayed at a given point, and its amplitude determines saturation.
The chap that was picking up ATV in Reigate on 405 lines would be picking up his out of area signal from the ATV Midlands transmitter in West Berkshire, hardly the midlands I know. Of course up until July 1968 he could have fairly easily picked up ATV London from the Croydon transmitter on Saturdays and Sundays. In those days Membury would have been ATV Midlands Mon to Fri and ABC Midlands at weekends. From July 1968 ATV/Central would have been on Membury every day until 405 lines was discontinued.
@ShymFan2007 OK a bit of history - BBC TV in UK started in 1936 using 405 lines VHF band-1 (channels 1-5). Then FM radio took up VHF band 2 from the early 50s. The first commercial services (ITV) started 1955, also 405 lines, but using VHF band-3 (channels 6-12). When 625 lines started in 1964, space was found in UHF bands 4&5 (channels 21-69) (channels 13-20 were not used in UK) The 625 UHF service took almost 20 years to be available throughout the country, and only then could the old VHF service be turned off. There are several funny stories of unmanned relay stations in the Scottish Highlands going off air and no-one ringing in to complain (cuz no-one was watching them). There is also a story that one such transmitter failed and the only viewer was a little old lady with an ancient set. The BBC decided it was cheaper to give the person a new set rather than repair the relay. I can't comment on the truth or otherwise of these tales. Anyway, When the 404 VHF service finally closed the UK Government thought they could raise a whole load of cash by auctioning off the spectrum to the highest bidder, thus VHF bands 1&3 were lost for broadcast use. Most of this spectrum in UK is now used for civic mobile services (Fire Police etc) and a small bit of band-3 carries digital audio (DAB). I agree many countries still use VHF for broadcasting but tend to have less broadcast presence on UHF. It all balances out I guess. The whistle U ask about is because the line oscillator frequency for 405 is about 10Khz whereas on 625 & 525 its more like 15-16 Khz The calculation is thus... Multiply the # of lines by 1/2 mains frequency = Line oscillator frequency. Thus 625 x 25 = 15,625Hz and 405 x 25 = 10,125Hz and 525 x 30 = 15,750hz Hope that helps-- Nigel
The 405 line B & W TV sets don't seem to give that bad a picture compared to 625 line ones, as long as the screen isn't too big in size and you view at a distance. The 405 line analogue system DID have some advantages over the 625 line system. Less bandwidth was needed for 405 lines, so more broadcast channels could be allocated on VHF Band I and III than using 625... the signal coverage area was better because of lower channel bandwidth AND the use of VHF instead of UHF, so less transmitters were needed for national TV coverage. Disadvantage of 405 line system over 625 lines: noticeable lower picture resolution, more prone to electrical interference, large bulky VHF antennas needed on roof which would blow down during storms. 405 lines was an advanced TV system for it's day (1930s)
Is this a Dynatron TV47V? If so I've just picked one up from t'uther side o' t'Pennines, in a village called Mirfield, virtually right underneath Emley Moor!
Although I can't hear the CRT whistle of 525 & 625 lines TV which is 15+ KHz because of my age but at 10+ KHz from 405 lines TV I can still hear it clearly.
I recognised the set to the right of the Dynatron as being an early 60s dual standard Sobell which had a GEC chasis (both the same firm by that time). It has a radio type tuning scale for the 625UHF band.
Interestingly, in 1964 there were tv boxes converters on sale, for to watch BBC2 by these TV SETS for system A 405 (378) lines? Reciever system I 625 (576) lines at UHF - VHF modulator for system A 405 (378) lines. Or should have to buy new TV SET with 2 tuners (in period 1964-November 1969)?
There were some converter boxes that would convert the frequency down from UHF to VHF & visa versa. They were sometimes needed for communal aerial systems in block of flats. I remember one model called "The Televerta" However its most unlikely that anything was available that would convert line standard. After 1970 the BBC distributed all TV over the national network at 625 lines and used an enormous device the size of a large wardrobe at each of its many 405 transmitters to convert the signal down (I know how big it was I've seen one). Back in the 60s, before any modern digital tech, a domestic device doing the same thing would have been impossible.
Never be a Gerry wells even with the funny glasses. Went to see Gerry 1994 took a large video camera for a private tour of his radios and part interview never been seen publicly
Met him there early nineties, amazing collection of stuff, the cellars were chock full of rare valves etc, only guy i knew who had a rack mounted standards converter in his bedroom!, we were even fed and watered with sausage sandwiches etc, i never saw the valve repair set-up though, perhaps that was later.
Because a) there are more than several 405-line TVs running in that room, so the 10.125KHz line whistle is actually coming from many sets, therefore amplifying the sound, and b) it was quite easy to get used to the sound. A few weeks after I had finished restoring my first 405-line set, I'd never notice it.
Lovely to see the old 405tv working again. Excellent. Thanks guys
Great to see this video - thanks for posting it! I remember Gerald Wells and the museum - amazing that he manufactured his own valves in the workshop in his garden.
From recollection, ITV Midlands (ATV and ABC) was broadcast on VHF channel 8 from the Lichfield transmitter, whilst BBC Midlands TV was on VHF channel 4 from Sutton Coldfield. I'm not sure why the two TV channels weren't co-sited.
Love to visit the museum. Lovely
that high pitched squeal damn havent heard that for years!
Lovely old radios great stuff
Loved hearing that Line Whistle again and all that lovely line structure brought back Childhood Memories.
Not really a difference between VHF and UHF, but rather a difference between PAL and NTSC(Designed by RCA). In the US, there were so many B/W TVs sold nationally by 1954(year of NTSC adoption) that anything in the way of color broadcasting that was not compatible with the existing standard would be all but rejected by the public and manufacturers, note the earlier FCC adoption of the incompatible CBS field sequential color system, CBS even with the government's grace couldn't get manufacturers to sign on. The British and Europe only started thinking about color a decade later. By the 1960s, the 405 line system was very dated, having been inferior all along to the US system, it didn't really make sense to build color on top of it like NTSC, and with the limited bandwidth allotted between channels, I'm not sure it was even possible. Since they were dropping the 405 line system all together, it only made sense to solve any remaining issues with NTSC and tailor it for the 50hz power frequency by having 625 lines at 25 times per second instead of 525 at 30 times per second, ignoring interlacing. The UK kept simultaneously broadcasting in 405 line for years after the PAL flip, kind of like what we did here with the digital transition. VHF and UHF are just frequency bands.
The high pitch is the horizontal scanning rate of a 405 line set,
(405 lines)*(25 frames per second)= 10.125kHz, the sound you are hearing. The higher pitch out of NTSC sets is 15.75kHz, it is just as loud, just that ones ears roll off the higher frequency.
What a fantastic video of a fantastic place, the televisions actually work and are switched on. It's looks like my bedroom in the 70's and 80's! I bet all those valves make that place warm. I see you had to use RUclips's image stabilization, so much to look at and so exciting you couldn't keep the camera steady Frank, haha! When conditions were right and with a motorised VHF Band III loft aerial I could receive ATV in Reigate, the signal had to come over the North Downs. No idea which transmitter it was from, I can't remember the channel number. The video brings back good memories for me but for one thing I'm glad to see the back of, the high pitch whistle (10.125KHz I believe), it's still ringing in my ears after watching the video!
the V W M . in Rosendale Road was a fantastic place. G W even had a machine for re-constructing and re-vacuuming valves in a subsidiary shed in the garden.
At an early age in the 60s, grandmother's house was the only place to watch tv. I was so fascinated by the lopt ringing, test cards and tv dxing. Some weather conditions enabled other far off regions of itv Stations to be received. Wonderful times and memories of the good old 405 turret channel changer. Sadly I have no interest in todays all singing and dancing smart tv's.
I love glass television sets, the rounder the better. Unfortunately in New Zealand where I am, the older sets are rare and nothing earlier than 1960 seems to be available, being the year transmission of the NZBC began its b&w service. Color didn't begin til 73 and I well remember going to the trades fair in Wellington to get my first glimpse of a color set. Magic.
@ShymFan2007 Because the (colour) TV techonology at the time was very expensive to implement and New Zealand had a relatively small population with a less prosperous economy than now..... the BBC spent a fortune switching over to colour in the late 1960s, and only the rich could afford the first colour TV sets in the UK, in fact many people rented black and white TV sets at the time
Lovely old stuff . It was strange to see modern digital break up on one. I love how you could see the globe rotation on the scope.
The waveform monitor is displaying two lines of picture information - line sync pulse followed by the colour burst superimposed on the back porch, then video information (luminance and chrominance together), ending with the front porch.The colour burst is a sample of the subcarrier oscillator from the source, which provides the phase and amplitude reference for the QAM modulated chrominance signal during the active line period. The phase of the chrominance signal determines the hue that is displayed at a given point, and its amplitude determines saturation.
Yes that's what I was trying to explain in the video - but rather badly.
The chap that was picking up ATV in Reigate on 405 lines would be picking up his out of area signal from the ATV Midlands transmitter in West Berkshire, hardly the midlands I know. Of course up until July 1968 he could have fairly easily picked up ATV London from the Croydon transmitter on Saturdays and Sundays. In those days Membury would have been ATV Midlands Mon to Fri and ABC Midlands at weekends. From July 1968 ATV/Central would have been on Membury every day until 405 lines was discontinued.
@ShymFan2007 OK a bit of history - BBC TV in UK started in 1936 using 405 lines VHF band-1 (channels
1-5). Then FM radio took up VHF band 2 from the early 50s. The first commercial services
(ITV) started 1955, also 405 lines, but using VHF band-3 (channels 6-12).
When 625 lines started in 1964, space was found in UHF bands 4&5 (channels 21-69)
(channels 13-20 were not used in UK) The 625 UHF service took almost 20 years to be
available throughout the country, and only then could the old VHF service be turned off.
There are several funny stories of unmanned relay stations in the Scottish Highlands going
off air and no-one ringing in to complain (cuz no-one was watching them). There is also a
story that one such transmitter failed and the only viewer was a little old lady with an
ancient set. The BBC decided it was cheaper to give the person a new set rather than repair
the relay. I can't comment on the truth or otherwise of these tales.
Anyway, When the 404 VHF service finally closed the UK Government thought they could
raise a whole load of cash by auctioning off the spectrum to the highest bidder, thus VHF
bands 1&3 were lost for broadcast use. Most of this spectrum in UK is now used for civic
mobile services (Fire Police etc) and a small bit of band-3 carries digital audio (DAB).
I agree many countries still use VHF for broadcasting but tend to have less broadcast
presence on UHF. It all balances out I guess.
The whistle U ask about is because the line oscillator frequency for 405 is about 10Khz
whereas on 625 & 525 its more like 15-16 Khz The calculation is thus... Multiply the # of
lines by 1/2 mains frequency = Line oscillator frequency.
Thus 625 x 25 = 15,625Hz and 405 x 25 = 10,125Hz and 525 x 30 = 15,750hz
Hope that helps-- Nigel
The 405 line B & W TV sets don't seem to give that bad a picture compared to 625 line ones, as long as the screen isn't too big in size and you view at a distance. The 405 line analogue system DID have some advantages over the 625 line system. Less bandwidth was needed for 405 lines, so more broadcast channels could be allocated on VHF Band I and III than using 625... the signal coverage area was better because of lower channel bandwidth AND the use of VHF instead of UHF, so less transmitters were needed for national TV coverage. Disadvantage of 405 line system over 625 lines: noticeable lower picture resolution, more prone to electrical interference, large bulky VHF antennas needed on roof which would blow down during storms. 405 lines was an advanced TV system for it's day (1930s)
Is this a Dynatron TV47V? If so I've just picked one up from t'uther side o' t'Pennines, in a village called Mirfield, virtually right underneath Emley Moor!
Although I can't hear the CRT whistle of 525 & 625 lines TV which is 15+ KHz because of my age but at 10+ KHz from 405 lines TV I can still hear it clearly.
try 16khz sine in audacity, you will hear it.
@@Synthematix Or a harmonic of the fundamental?
I recognised the set to the right of the Dynatron as being an early 60s dual standard Sobell which had a GEC chasis (both the same firm by that time). It has a radio type tuning scale for the 625UHF band.
My childhood was viewed through a 405 line telly. I read that Holme Moss transmissions could be picked up in the east of Ireland and East Anglia.
Ps, Membury is the transmitter referred to in West Berkshire.
My Grandad had a 405 line Set very similiar to it
Interestingly, in 1964 there were tv boxes converters on sale, for to watch BBC2 by these TV SETS for system A 405 (378) lines? Reciever system I 625 (576) lines at UHF - VHF modulator for system A 405 (378) lines. Or should have to buy new TV SET with 2 tuners (in period 1964-November 1969)?
There were some converter boxes that would convert the frequency down from UHF to VHF & visa versa. They were sometimes needed for communal aerial systems in block of flats. I remember one model called "The Televerta" However its most unlikely that anything was available that would convert line standard. After 1970 the BBC distributed all TV over the national network at 625 lines and used an enormous device the size of a large wardrobe at each of its many 405 transmitters to convert the signal down (I know how big it was I've seen one). Back in the 60s, before any modern digital tech, a domestic device doing the same thing would have been impossible.
@@Actranuk Thank yoy very much for answer.
@@Actranuk .When I used to visit the V W M . Gerry wells had the 625/405 converter in his back bedroom. it was in a 19" rack about five feet high.
Should have adsded that it was the one from B B C crystal Palace.
The Dynatron is the name of an electronic oscillator crkt built around vacuum tube technology.
Never be a Gerry wells even with the funny glasses. Went to see Gerry 1994 took a large video camera for a private tour of his radios and part interview never been seen publicly
Met him there early nineties, amazing collection of stuff, the cellars were chock full of rare valves etc, only guy i knew who had a rack mounted standards converter in his bedroom!, we were even fed and watered with sausage sandwiches etc, i never saw the valve repair set-up though, perhaps that was later.
Is the venue of this video a museum, and if so where is it, and is it open to the general public or by application or invitation only?
The venue was the home of Gerald Wells, Google "British Wireless and television museum" it is in Dulwich, South London
That 10Khz Horizontal pulse sound is absolutely awful...how could watch anyone ever TV on a thing like this...
Because a) there are more than several 405-line TVs running in that room, so the 10.125KHz line whistle is actually coming from many sets, therefore amplifying the sound, and b) it was quite easy to get used to the sound. A few weeks after I had finished restoring my first 405-line set, I'd never notice it.
They sound beautiful to me !
Святой человек!