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Broadcast Analogue TV Channel Frequency Allocations and Numbering

 
Synchrodyne
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Broadcast Analogue TV Channel Frequency Allocations and Numbering

This thread is an adjunct to those extant on Analogue TV Receiver Intermediate Frequencies ( https://www.radios-tv.co.uk/community/black-white-tvs/television-receiver-intermediate-frequencies/) and Analogue Television Broadcast Transmission System Letter Designations  ( https://www.radios-tv.co.uk/community/black-white-tvs/analogue-television-broadcast-transmission-system-letter-designations/).

During the course of ferreting out information for these threads, I discovered that in the European case at least, the development of TV channel frequencies and the numbering thereof was not as simple as one might expect.

Channel dimensions are determined by the choice of TV system, and in some cases have been paramount in defining TV parameters. And channel frequency allocations and IFs are interrelated, and this interrelation is part of the geographical channel allocation process.

One apparent oddity that caught my attention and suggested further study was that whereas the ITU was involved in defining and numbering the European UHF TV channels, something that happened at the 1961 Stockholm European VHF-UHF planning meeting (ST61), it studiously stayed away from anything to do with numbering of the European VHF channels, both at the 1952 Stockholm European VHF planning meeting (ST52) and again at ST61.

The American case (including the “what happened to channel 1” question) was relatively simple, and has been well covered in the literature, so for now is set aside.

As a starting point, here is a page from a Wireless World (WW) 1959 March article “European Television Stations – Survey of the Continent’s Network”. Listed are the VHF TV channel sets for the UK, Western Europe, Eastern Europe and France. (Those for Italy and East Germany were detailed later in the text of the article, and I’ll mention them later on.)

WW 195903 p.109
from WW 195903 p.109

There were no major surprises in that list, but worth noting are:

In the UK case, channel 13 was not included.

In the Western European (CCIR) case, unsurprisingly there was no channel 1.

In the French case, there was no channel 1, but channel 3 – which was never used – was still listed.

As best I can tell, those VHF channel numbers were allocated by in-country authorities/agencies, or by groups of such organizations acting together. Certainly I can find no evidence that either the ITU or CCIR were involved. On the other hand, channel numberings can be found in some of the individual country submissions to ST52 and ST61.

More than that though, for each channel group in that WW 1959 March article the numbers were preceded by letters that fairly obviously referred to the geographies in which they were used, thus B for Britain, E for Europe, O for the OIRT (Eastern Europe) group, and F for France. Only recently have I pondered the origin of those prefixes. One may assume that there was no need for them to be used in-country, and that they were not applied by in-country authorities/agencies. They do not appear in ITU or CCIR documents, not surprising considering that neither was involved in European VHF channel numbering. They could simply be informal designations that acquired a life of their own. But if they are more formal in nature, then I see the EBU as being the prime suspect. The EBU technical archives are not as accessible on-line as those for the CCIR and ITU, so this lead is a difficult one to follow.

As mentioned above, the ITU did define and number the European UHF TV channels, this plan being during the ITU ST61 meeting, and recorded in the Final Acts thereto, on page 26. The “E” prefix was not included.

ITU ST61 Final Acts p.26

The “O” prefix used for the Russian/East European VHF channels appears to have been changed to “R” at a later date. Other prefixes have also been used, including “A” for the American channels, “C” for the Chinese channels, “J” for the Japanese channels, “M” for the Moroccan channels and “NZ” for the New Zealand channels.

Following postings will include a look at what may be derived from the ITU ST52 documents in terms of the development of the British, French, Italian, Western European and Eastern European channelling systems respectively.

Note that this survey covers broadcast transmission channels only – I have made no attempt to include the later cable channels.

Cheers,

Steve

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Topic starter Posted : 29/03/2019 2:25 am
Synchrodyne
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Broadcast Analogue TV Channel Frequency Allocations and Numbering – UK VHF Channels

Here is the part of the UK submission to ITU ST52:

ITU ST52 Doc 16 E UK TV p.01
ITU ST52 Doc 16 E UK TV p.04
ITU ST52 Doc 16 E UK TV p.03
ITU ST52 Doc 16 E UK TV p.02

A couple of observations may be made. Firstly, at that time the Band III channels were numbered in their own sequence, from 1 through 8. Secondly, they ran from the bottom edge of Band III, 174 MHz, though 214 MHz, although it was noted that they could be moved upwards by no more than 2 MHz if required by international agreement.

ST52 Final Acts shows that these channels were moved up by 2 MHz as part of the European VHF plan, thus occupying 176 through 216 MHz. I assume that the renumbering, to be consecutive with the Band I channels, was done after ST52 by the appropriate authority, probably the GPO although I’d expect working with the BBC and the TAC. The earliest reference I have found to the definitive UK Band III channel numbers is in WW 1953 August, wherein channels 7 and 8 were mentioned.

WW 195308 p.365

The ST52 plan provided for use of all of the Band III channels, including channel 13. The non-inclusion of the latter in the WW 1959 March article may well have reflected the fact that at the time, it not yet been cleared of other users so was not yet available for TV.

Numbering of the UK Band I channels seems to have happened in the 1949-49 period. The earliest mention I have found in WW is 1949 May. This channelling plan was based upon the decision to adopt asymmetric sideband transmission for all new transmitters.

WW 194905 p.175

The channel frequency details for the Sutton Coldfield transmitter had been announced in WW 1948 November, although at the time there was no mention of the channel number.

WW 194811 p.411 BBC TV Birmingham

Cheers,

Steve

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Topic starter Posted : 29/03/2019 2:38 am
Synchrodyne
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Broadcast Analogue TV Channel Frequency Allocations and Numbering – France VHF Channels

Here is part of the French submission to ST52:

ITU ST52 Doc 52 E Annex 1 France p.28
ITU ST52 Doc 52 E Annex 1 France p.27

This described the proposed tête-bêche channelling system for Bands I and III. At that time, the “normal” channels were numbered 1 and 2 (Band I) and 3 through 6 (Band III). The “inverted” channels were numbered 1’ and 2’ (Band I) and 3’ through 6’ (Band III). Thus there were four channels in Band I, and 8 in Band III.

The ST52 allocations for Band I in particular included transmitters in what were channels 1 and 2, but none in what was channel 1’ and just one in what was channel 2’, although of course these were shown only by frequency.

Presumably the definitive channel numbers, in a single sequence, were assigned after ST52. The “normal” channels received the even numbers, whereas the “inverted” channels received the odd numbers.

channel 1 became channel 2.
channel 1’ was not assigned at ST52, and never used, so may not have been assigned a new number, but if so, logically it would have been channel 1.
channel 2 became channel 4.
channel 2’ became channel 3, but even though assigned at ST52, it was in fact never used.
channels 3, 4, 5 and 6 became channels 6, 8, 10 and 12 respectively.
channels 3’, 4’, 5’ and 6’ became channels 5, 7, 9 and 11 respectively.

(New) channel 3 became unusable, or at least very difficult to use, following the adoption of the standard IF channel with 28.05 MHz VIF and 39.2 MHz SIF. This IF required infradyne operation for the “inverted” channels, but on the other hand the Band I channels required supradyne operation. So there was mutual exclusivity (barring for example double conversion). The same would have applied to new channel 1 had its use been planned. Thus in practice there were just two Band I channels used for French 819-line television, namely 2 and 4, both of the “normal” type.

The French ST52 submission also included comments on its existing 819-line Band III transmitters at Paris and Lille, and its 441-line transmitter at Paris.

ITU ST52 Doc 52 E Annex 1 France p.34
ITU ST52 Doc 52 E Annex 1 France p.33

At the time the Paris and Lille 819-line transmitters were seen as being “extreme offset” cases, presumably referred to channel 4 (later channel 8). In the definitive numbering system, this extreme offset channel became number 8A. Evidently the original French 819 plan had involved just three channels in Band III, according to Kerkhof and Werner:

Kerkhof & Werner p.81

In the case of the Paris 441-line transmitter, the required separation distances required for 819-line channels 1 and 1’ were recorded. The 441-line transmitter did not appear to have its own channel number. This was shown in the channel allocation proposal that the French delegation took into ST52:

ITU ST52 Doc 52 E Annex 1 France p.32
ITU ST52 Doc 52 E Annex 1 France p.31

Given that the definitive French VHF channel numbering system started at channel 2, then absent the historical information, a legitimate question was “what happened to French channel 1?”. The conventional wisdom appears to be that channel 1 described the band used by the Paris 441-line transmitter. But the foregoing information might contradict that conventional wisdom.

A prerequisite for developing an answer to “what became of French channel 1” is answering the question “what was French channel 1?” From the ST52 submission, it could have referred to either what was provisionally known as channel 1, and which became the channel 2 in the definitive listing, or to what was provisionally known as channel 1’, and which logically would have become channel 1 in the definitive listing had it been assigned for use.

Possibly, when the definitive numbers were assigned, the French authorities might have decided that as that series would not include what had been provisionally identified as channel 1’, the channel 1 moniker was instead assigned to the 441-line channel. But that would have been a change from the earlier plan not to number the 441-line channel. As there was only one such, numbering was not really needed. Given the strength of the evidence in favour of the notion that whatever channel 1 was, it was not the 441-line channel, I think that there would need to be found “hard” evidence to support the conventional wisdom. Also, the 441-line channel was “normal”, that is vision carrier high, so if numbered at all, it might have been expected to have been given an even number in the definitive sequence.

ITU ST52 Doc 52 E Annex 1 France p.37
ITU ST52 Doc 52 E Annex 1 France p.36

Following the cessation of system E VHF transmissions in 1984, Bands I and III were re-used for system L transmissions, with a different set of channels. This will be covered later in this series.

Cheers,

Steve

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Topic starter Posted : 29/03/2019 2:47 am
Synchrodyne
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Broadcast Analogue TV Channel Frequency Allocations and Numbering – Italy VHF Channels

The Italian submission to ITU ST52 included its own set of VHF channels, as shown in these documents:

ITU ST52 Doc 32 E Italy TV p.03
ITU ST52 Doc 32 E Italy TV p.02
ITU ST52 Doc 32 E Italy TV p.01

This arrangement of channels, just five of them, was certainly different to that proposed by other Western European countries that were planning to use the 625-line system. At that time no numbers or other designations were shown for these channels.

The 81 to 88 MHz channel stemmed from the 1949 Torino experimental transmitter, supplied from the USA, and which had used channel A6, 82-88 MHz, with parameters that were later associated with system N. One assumes that it was simply expanded downwards to 81 MHz when it was decided to use a 7 rather than a 6 MHz channel. Whilst the planning covered the contingency that this out-of-band channel would not be agreed to by the ITU, in fact it was accepted and covered by a special protocol to the ST52 Final Acts.

The ST52 list of European TV channel allocations included the following for Italy:

61-68 MHz – one of the original 5, and corresponding to European channel 4.
81-88 MHz – one of the original 5.
174-181 MHz – one of the original 5, and corresponding to European channel 5.
191-198 MHz – not one of the original 5, but proposed for use in the event that 81-88 MHz was unavailable; not aligned with any European channel. Even though 81-88 MHz was available, it was used anyway.
200-207 MHz – one of the original 5, not aligned with any European channel.
209-216 MHz – one of the original 5, aligned with what became European channel 11.

The original list had included 218-225 MHz, not as one of the primary 5, but thought to be needed. Possibly the addition of 191-198 MHz obviated the need for it. The 218-225 MHz channel was outside of Band III and not aligned with any European channel.

Along with its original channel plan, Italy had also set 40-47 MHz as its standard TV IF channel, possibly derived from the American 41-47 MHz IF channel. This was largely in Band I, and effectively precluded the use of the lower end of that Band in Italy.

The WW 1959 March article on European TV showed an enlarged list of Italian TV channels, which by that time had acquired alphabetical designations, as follows:

A 52.5-59.5 MHz
B 61-68 MHz, same as European channel 4.
C 81-88 MHz
D 174-181 MHz, same as European channel 5.
E 182.5-189.5 MHz
F 191-198 MHz
G 200-207 MHz
H 209-216 MHz, same as European channel 10.

Channels A and E were evidently added after ST52. Channel E split the difference between channels D and F, with 8.5 MHz separation from each. Channel A was 8.5 MHz below channel B.

Presumably Italy chose letter designations to avoid any confusion with the numbered Western European channels.

Much later on, channels H1 (216-223 MHz) and H2 (223 to 230 MHz) were added, these corresponding to channels E11 and E12 respectively.

Cheers,

Steve

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Topic starter Posted : 29/03/2019 2:50 am
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Broadcast Analogue TV Channel Frequency Allocations and Numbering – Western Europe VHF Channels

Firstly, here is part of the German submission to ST52:

ITU ST52 Doc 52 E Annex 1 Germany p.53
ITU ST52 Doc 52 E Annex 1 Germany p.54
ITU ST52 Doc 52 E Annex 1 Germany p.55

The first point to note is that at that time, the Band I and Band III channels each had their own numbering system, beginning at 1. Thus the Band I channels were 1 through 4, and the Band III channels were 1 through 6. Where distinction between the two bands was needed, the forms such as channel I/3 and channel III/5 were used.

The second point is that the submission was based upon their being four channels available in Band I, including channel 1 with vision carrier at 41.25 MHz, just inside the lower limit of Band I. Presumably it was thought that this would be acceptable, despite the fact that the vestigial vision sideband would extend below the 41 MHz Band I lower limit by 0.5 MHz. It seems unlikely that a submission that included a 100 kW erp channel 1 transmitter would have been made in the absence of a belief that it would be so.

Secondly, here is part of the Swiss submission to ST52:

ITU ST52 Doc 52 E Annex 1 Switzerland p.65

One may see that the Swiss were being more circumspect than the Germans. They had not assumed the availability of four Band I channels, but if that was to be the case, then they had an alternative plan that would use the four channels, numbered 1 through 4. They recognized that this would require the enlargement of Band I.

None of the submissions from other countries planning to use the CCIR TV system (later system B) or derivatives of it (as in Belgium) reveal anything material in respect of channel numbering.

Anyway, it does seem that the pre-ST52 notion that Band I would have four 7 MHz channels numbered from 1 through 4 was well enough entrenched that it determined the way that what became the E-channels were definitively numbered.

In fact the output of ST52 showed an allocation for three transmitters in Yugoslavia, with 41.25 MHz vision and 46.75 MHz sound, that is what the Germans had labelled as channel 1. I understand that these were not taken up.

ST52 Final Acts p.17
ST52 Final Acts p.18
ST52 Final Acts p.96

Not only that, but it also showed an allocation of 42.25 MHz vision, 46.75 MHz sound for Braunschweig, West Germany. This was a 6 MHz channel with 4.5 MHz intercarrier, so if it had been used, it would have bene a difficult case when all of the other channels were 7 MHz with 5.5 MHz intercarrier. It is not surprising that it was not taken up. But it may have been the source of the idea, found in some 1950s texts, that channel 1 was of 6 MHz width with a 4.5 MHz intercarrier.

There is no evidence that numbering the Band III channels in the same sequence as the Band I channels, and therefore starting at channel 5 was envisaged before ST52. I’d guess that it happened soon after; the logic, as compared having them numbered 1 through 6, was inescapable.

The ST52 output also included allocations, for Belgium, Germany and Switzerland, a 7 MHz channel just above the top edge of Band III, at 216 to 223 MHz. This became channel 11.

Channel 12 in the sequence, 223 to 230 MHz, was added much later.

Cheers,

Steve

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Topic starter Posted : 29/03/2019 2:55 am
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The 6 MHz channel width and 4.5Mhz vision sound spacing although 625/50 initially made me think it was to allow US service personnel to use USA TV’s imported by the services stores. The line and frame would probably be within adjustments.

Unfortunately this is probably not the case,  Braunschweig would have been in the UK section at that time.

It was a thought, obviously not a good one.

Frank

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Posted : 29/03/2019 9:30 am
Synchrodyne
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Quite a logical thought, really. The 625/50 system in a 6 MHz channel, later known as system N, was already in use at the time. That was in Argentina, where the TV service had started around 1951 September. In that case, the apparent objective was to fit the 625/50 system into a standard American TV channel, so that there was then no frequency conflict with the neighbouring South American countries, the majority of which had 60 Hz electricity supplies and so used the American 525/60 TV system (later system M). Also of course, 625/50 in a 6 MHz channel had been used for the American-supplied 1949 experimental transmitter in Torino. So as a system, it was older than the CCIR version in a 7 MHz channel.

Cheers,

Steve

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Topic starter Posted : 30/03/2019 12:16 am
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Broadcast Analogue TV Channel Frequency Allocations and Numbering – Eastern Europe VHF Channels

Eastern Europe generally adopted the original (Russian) 625-line TV system with an 8 MHz channel rather than the bandwidth-restricted CCIR system with 7 MHz channel that was widely used in Western Europe. Thus its channel allocations and numbering thereof would necessarily be different. However, the Russian submission to ST52 was radically different, as shown in these ST52 documents:

ITU ST52 Doc 33 E USSR p.01
ITU ST52 Doc 33 E USSR p.02
ITU ST52 Doc 33 E USSR p.03
ITU ST52 Doc 33 E USSR p.04

The key component was that Band III would be extended downwards to 144 MHz, whereafter nine 8 MHz channels could be accommodated in the range 144 to 216 MHz. These would be the primary channels used for the TV service, and were numbered 1 through 9.

Of those, channels 5 though 9 were fully within the boundaries of Band III, and occupied the range 176 to 216 MHz.

Additionally, three Band I TV channels were proposed, identified as Sub Band channels I, II and III, although elsewhere in the document also referred to as SB1, SB2 and SB3. SB1 and SB2 were adjacent, at 40.5 to 48.5 and 48.5 to 56.5 MHz respectively. SB3 was slightly separated, at 58 to 66 MHz.

The lower edge of SB1 was below the lower edge of Band I by 0.5 MHz, but that was essentially the guard band, with the vestigial sideband nominally ending at 41.0 MHz.

It was planned that the gaps on either side of SB3, namely 56.5 to 58, and 66 to 68 MHz, would be used for additional FM broadcasting stations. At that time, the USSR was still planning on using Band II, 87.5 to 100 MHz, as its main FM broadcasting band, and was also planning on using the customary ±75 kHz deviation.

The subsidiary nature of Band I in this plan reflected concerns about its sometimes long-distance propagation and the resultant mutual interference problems. In the European context that was probably not unfounded, although elsewhere in the world Band I TV channels were often used to maximum advantage from a transmitter coverage viewpoint.

Evidently the Band III downward extension proposal was not accepted at ST52. The Final Acts from that meeting included Eastern European TV transmitters in Band I channels that corresponded to SB1, SB2 and SB3, and in Band III channels that corresponded to 5 through 9. Also included were European FM allocations in the 56.5 to 58 and 66 to 68 MHz sub-bands, as well as in Band II.

Whether any of the ST52 allocations were actually used in Eastern Europe is unknown. There was a major change of plan. Exactly when that change was made I have not been able to ascertain, but it was probably fairly soon after ST52.

The key component of the new plan was that the band 76 to 100 MHz, inclusive of the whole of Band II, 87.5 to 100 MHz, would be used to accommodate three 8 MHz TV channels. In part, the appropriation of 76 to 87.5 MHz could be seen as a replacement for the previously proposed downward extension of Band III that was not obtained.

Of the original Band I TV channels, SB1 was not used, but SB2 and SB3 were retained unchanged.

Within Band III, there were five channels within the range 174 to 214 MHz, these being 2 MHz lower than the previously proposed channels 5 through 9. There were two additional channels in the range 214 to 230 MHz. Whether both of these were in the original version of the new plan or added later is unknown. But both were in place by 1959. ST52 had endorsed the use of the 216 to 223 MHz channel in certain Western European cases, so against this at least the 214 to 222 MHz Eastern European channel should have been acceptable.

All of these new channels were numbered consecutively in one sequence. Channels 1 and 2 were previously SB1 and SB2. The three Band II channels were 3 through 5. And the Band III channels were 6 through 12. These were shown in the WW 1959 March article:

from WW 195903 p.109 OIRT TV Channels

With Band II no longer available for FM broadcasting, the range 66 to 73 MHz was assigned for this purpose. This was inclusive of the previous 66 to 68 MHz sub-band. It would appear that the use of the 56.5 to 58 MHz sub-band was abandoned at this stage. The ST61 Final Acts list shows Eastern European Band I FM stations starting at 65.525 MHz, so it could have been that the “FM Band”, as it were spanned the range 65.5 to 73 MHz, meaning that there was overlap with TV channel 2, whose sound carrier was at 65.75 MHz, and whose vision sideband extended to 65.25 MHz. Also apparently coincident with this change was the reduction in FM maximum deviation to ±50 kHz, the same as used for TV sound in both Eastern and Western Europe. Just why this was done is not clear, and it did have later consequences when it came to adding stereo. The early history of FM broadcasting basic parameters is not fully transparent, but that is a separate topic.

It may be seen that Eastern Europe was then using for broadcasting all of the 68 to 87.5 MHz gap between Bands I and II except for 73 to 76 MHz. That small break was to protect the international aviation ILS beacon frequency of 75 MHz. The use of this out-of-band frequency range was eventually regularized at an ITU Special Regional Conference in Geneva in 1960. The Final Acts list from this meeting covered only transmitters in, or partially in the 68 to 73 and 76 to 87.5 MHz bands. FM transmitters within Band I, and TV transmitters within Band II were covered in the ST61 Final Acts list.

The original Band I TV allocations, SB1, SB2 and SB3 are worthy of further comment. Given the concerns about Band I propagation and mutual interference, which was probably worse at the lower end of the band, one might have expected a sequence in which the highest channel was up against the top edge, 68 MHz, so that the three occupied the range 44 to 68 MHz. Instead though, channel SB1 was more-or-less adjacent to the lower end of Band I, starting at 40.5 MHz, but with its “active” part starting at 41 MHz. SB2 was adjacent to SB1, but SB3 was somewhat separated from both the upper edge of SB2 and the upper edge of Band I, with the gaps to be used for FM broadcasting. Why not then have SB3 adjacent to SB2, which would have placed it in the range 56.5 to 64.5 MHz, leaving a continuous range of 64.5 to 68 MHz for FM. However, it would appear that the plan was to use those small Band I segments for FM broadcasting in the same areas in which channels SB2 and SB3 were to be used. That is, 56.5 to 58 MHz would be used with channel SB2, and 66 to 68 MHz with channel SB3. Presumably that would have been seen as advantageous from a transmission viewpoint. The FM carriers would look somewhat like additional sound carriers with the TV broadcast. That the SB2 and SB3 channel details were carried over to the post-ST52 plan without change suggests that there may have been a small number of transmitters already using these, making any frequency shift undesirable.

The Eastern European VHF TV channels were listed in the Poland submission to ITU ST61:

ITU ST61 Doc 22 E p.03
ITU ST61 Doc 22 E Annex p.01 OIRT TV Channels

Note that they were simply numbered 1 through 12, without an “O” prefix. This tends to confirm the notion that the letter prefixes to channel numbers were not assigned by the originating agencies, but either added by another organization, or used informally.

Although the channelling plan was used generally in Eastern Europe, East Germany did differently, as will be covered in a following posting.

Cheers,

Steve

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Topic starter Posted : 30/03/2019 12:29 am
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How times change, the first page third paragraph of the USSR submission is interesting from an historical point. One TV channel and two VHF radio channels with the possibility in some areas for an additional TV and radio channel.

Obviously not the same material and broadcaster, each area would have its own but only one or if you are lucky two stations in any given area. Compared with today’s hundreds of channels. Not that I am saying quantity is in anyway quality.

It was twelve years after the ST52 that the UK started to implement a third TV channel, albeit on UHF.

The USSR VHF FM band always puzzled me, at least this explains in some part that reason.

The thread apart from being educational is fascinating, thank you Steve.

Frank

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Posted : 30/03/2019 9:05 am
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Thanks Frank!

Indeed things were very different back in the early 1950s, and for quite a bit after that.

Re the Russian/Eastern European case, I have just found a bit more information – something I should have looked at before writing the above – and will include this in my next post.

Cheers,

Steve

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Topic starter Posted : 31/03/2019 6:44 am
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Broadcast Analogue TV Channel Frequency Allocations and Numbering

The VHF and UHF broadcasting bands were first delineated, in an international sense, at the ITU 1947 Atlantic City meeting, although individual countries had previously made their own assignments, quite extensively so in the case of the USA. The ITU frequency allocation process covered all applications, not just broadcasting, in the range 10 kHz to 10 500 MHz.

For ITU Region 1, inclusive of Europe, the assigned VHF and UHF broadcasting bands were:

41 to 68 MHz

87.5 to 100 MHz

174 to 216 MHz

470 to 585 MHz

610 to 960 MHz

These bands appear to have been unnamed in the pertinent ITU documents, notwithstanding the fact that the familiar Bands I through V names are typically assigned as deriving from the ITU work. But that is another “mystery”….

There were multiple footnotes covering exceptions, and many of these covered the use of broadcasting bands, or parts thereof, for non-broadcasting purposes., such as happened with Bands II and III in the UK.

But a small number of those footnotes delineated broadcasting bands outside those recorded above. These included 68 to 72 MHz and 76 to 108 MHz in the USSR. The latter of course encompassed European Band II, at 87.5 to 100 MHz.

ITU Atlantic City 1947 Annex p.46 E USSR 68 72 MHz
ITU Atlantic City 1947 Annex p.47 E USSR 76 108 MHz

To some extent these limits followed the North American (Region 2) precedent, where the bands in the same vicinity lowest band ran 44 to 50, 54 to 72 and 76 to 108 MHz, with the last-mentioned divided between TV below 88 MHz and FM above it.

Whether the USSR had specific plans for the VHF bands back in 1947 is unknown. But either way, the stage was set for its eventual use of 68 to 73 MHz for FM and 76 to 100 MHz for TV.

Against that, its ST52 submission which required Band III to be extended downwards, but kept Band I and Band II assignments within their Region 1 boundaries, may be seen as an effort to obtain a pan-European agreement in a situation where none of the other countries had Band I or Band II extensions. The USSR had assigned 216 to 260 MHz for radio navigation purposes, and initially may have been reluctant to look at having any broadcasting assignments in that band, hence the need to look downwards.

With its proposal not accepted – and probably most unlikely to have been accepted – it then reverted to what it saw as the optimal use of its 1947 allocations, at the same time unilaterally moving the upper limit of Band I slightly to 73 MHz, not using the 100 to 108 MHz section of Band II, and, notwithstanding its apparent previous position, unilaterally moving the upper edge of Band III out to 230 MHz. (That might have been done in two stages, with an initial step to 222 MHz.)

Regarding Band III downward extensions, the use of 162 to 174 MHz for broadcasting in France was footnoted in the Atlantic City 1947 annex. The whole 162 to 216 MHz band was accounted in the tête-bêche channelling system delineated in the French ST52 submission. One may wonder then why the apparent initial French 819-line TV channelling proposal covered only 174 to 216 MHz. Perhaps it was originally envisaged that the 819-line system might be more widely used in Europe, and so had to fit within the standard Band III limits.

ITU Atlantic City 1947 Annex p.50 E France 162 174 MHz

Cheers,

Steve

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Topic starter Posted : 02/04/2019 1:05 am
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The next ITU frequency allocation meeting was held at Geneva in 1959. By now the range of frequencies covered extended from 10 kHz to 40 GHz.

Here, the various European broadcasting deviations from the basic Region 1 allocations were recorded, either in the tables or in footnotes in the output from that meeting.

In particular, the Eastern European use of the 68 to 73 MHz and 76 to 87.5 MHz bands for broadcasting was noted. The 68 to 73 MHz segment included the extension to 73 MHz as compared with the 68 to 72 MHz recorded in the Atlantic City 1947 output.

ITU 1959 Geneva Radio Regulations p.60 Eastern Europe 68 to 87.5 MHz
ITU 1959 Geneva Radio Regulations p.61 Eastern europe 68 to 87.5 MHz

The countries involved were recorded as the USSR, as in 1947, with the addition of Albania, Bulgaria, Hungary, Poland, Roumania and Czechoslovakia. Eastern Germany was not included, as this country did somewhat differently when it came to TV broadcasting, as will be covered in a later posting.

Effectively, in Eastern Europe Band I covered 41 to 73 MHz, with 41 to 66 MHz used for TV and 66 to 73 MHz for FM. And Band II covered 76 to 100 MHz, and was used for TV only.

The 162 to 174 MHz downward extension at the lower end of Band III, previously recorded only for France, was now listed as being applicable as well to Monaco and Morocco. Monaco had followed France in its choice of the 819-line TV system and its associated channel frequencies. However, Morocco opted for 625 lines, and developed a unique set of Band III channel frequencies, to be covered in a later posting.

ITU 1959 Geneva Radio Regulations p.68 France, Monaco, Morocco 162 174 MHz

At the upper end of Band III, 216 to 223 MHz was shown as being used both for broadcasting and aeronautical radionavigation, varying by country. The inclusion of broadcasting was an addition, as compared with Atlantic City 1947. It legitimized, as it were, both existing Western European TV channel 11 (216 to 223 MHz) and existing Eastern European channel TV channel 11 (214 to 222 MHz).

223 to 235 MHz was shown as an aeronautical radionavigation band, but a footnote indicated that 223 to 230 MHz was also allocated to Austria and Switzerland for broadcasting on a permitted basis. This would appear to provide an approximate date for the inception of European TV channel 12 (223 to 230 MHz), which had not been included in the Wireless World 1959 March list.

ITU 1959 Geneva Radio Regulations p.69 Band III
ITU 1959 Geneva Radio Regulations p.70 223 230 MHz

Another footnote indicated that 223 to 230 MHz was allocated to broadcasting in Albania, Bulgaria, Hungary, Poland, Roumania, Czechoslavakia and USSR. This legitimized existing Eastern European TV channel 12.

Band III now effectively covered the range 162 to 230 MHz, although with restricted geographical use of the 162 to 174 and 223 to 230 MHz segments. It is interesting to note that in the output from the ITU ST61, Band III was referred to as the 162 to 230 MHz range.

Cheers,

Steve

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Topic starter Posted : 02/04/2019 2:15 am
Nuvistor liked
Synchrodyne
(@synchrodyne)
Reputable V-Ratter Registered

As already noted, the ITU 1959 Geneva meeting output included the upward extension of Band III, to 230 MHz, on a conditional basis.

The UK was evidently a potential user of at least part of the upward extension, although never an actual user.

The output from the ITU ST61 meeting included UK allocations for a channel with vision carrier at 219.75 MHz and sound carrier at 216.25 MHz, that is spanning 216 to 221 MHz. Logically this would have been channel 14, although as previously said, the ITU did not refer to the European VHF channel numbers.

ITU ST61 Final Acts p.150,151 UK Channel 14

The footnote specific to these assignments stated: “Stations to which this channel is assigned will not be brought into use until the aeronautical navigation and the United Kingdom radiolocation services, to which interference might be caused, cease to operate.”

ITU ST61 Final Acts p.292 UK Channel 14

Evidently “channel 14” was not needed, and probably was not cleared of other activities, and all required Band III transmitters were accommodated in channels 6 through 13.

Some other observations:

In the ST52 tabulation, UK channel 1 was shown as being 7 MHz wide, reflecting that at the time, it was of the double sideband form. Given that the lower edge of channel 2 was 48.0 MHz, then channel 1 logically extended from 41.0 to 48.0 MHz. With the sound carrier at 41.5 MHz, it had a 0.5 MHz lower guard band rather than the usual 0.25 MHz below the sound carrier, and no guard band above the upper edge of the upper vision sideband, which extended to 48.0 MHz. If one uses the norm of 0.5 MHz between the outer edge of a full vision sideband and the nearest sound carrier, then one could say that channel 1 had a 0.25 MHz upwards offset. Of course, it was originally delineated a decade or so before the ITU defined Band I as being 41 to 68 MHz in Region 1, and I imagine was taken into account when the Band I limits were worked out.

Basis the System A specification channel dimensions, the vestigial sideband version of UK channel 1 would have extended from 41.25 to 46.25 MHz.

By way of comparison, the single French channel used for its Paris 441-line transmitter, also double sideband, was described in the ST52 tabulation as being 7.6 MHz wide. Here the sound carrier was at 42.0 MHz, and the vision carrier at 46.0 MHz. The French submission to ST52 had noted that the vision transmitter occupied a band from 42 to 50 MHz. One suspects that the lower vision sideband would have been significantly attenuated at the sound carrier frequency of 42.0 MHz, so that, assuming symmetry, a vision band of 42.5 to 49.5 MHz would have been more realistic. On that basis, a 7.6 MHz channel would have allowed for a 0.1 MHz guard band below the sound carrier, with the channel extending from 41.9 to 49.5 MHz. Somewhat academic perhaps, but the French did have to plan for the fact that the 441-line channel overlapped with what became 819-line channel 2.

Cheers,

Steve

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Topic starter Posted : 17/08/2019 11:27 pm
Terry
(@terrykc)
Famed V-Ratter Rest in Peace

By the time that report was published there were large numbers of 13 channel TVs in the UK following on from the popularity of commercial TV and it would, no doubt, have taken quite a time to clear the space that channel 14 would have occupied. Also, the band planning for ITV could only have taken into account the original available bandwidth.

I doubt, therefore, there would ever have been a reason to use the extra channel given that no existing sets could receive it (although I'm sure I once saw a set with a 14 channel turret).

True, turret tuners could easily have Ch. 14 biscuits fitted but what about the vast number using permeability or incremental tuning?  Fireball tuners would have needed a completely new coil disc - assuming the Ch.13 coils couldn't be adjusted up a channel but there were only 13 positions, so another channel would have to have been dropped - but which one?

Did I dream that 14 channel turret? It certainly wasn't anything we sold.

When all else fails, read the instructions

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Posted : 19/08/2019 12:46 pm
Synchrodyne
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Reputable V-Ratter Registered

I imagine that the introduction of “channel 14” in the UK would have been problematical. Presumably whomever in the UK requested the allocations at ST61 was simply doing some hedging of bets.

That said, the original Cyldon TV12 TV front end of 1953 had coverage to 220 MHz, enough to include “channel 14”, although with only 12 positions, some compromise would have been necessary, e.g. wide-range fine tuning to allow the two highest frequency biscuits to cover channel pairs, 11-12 and 13-14 respectively. Initially the TV12 would have been aimed at the export market, possibly with channel E2 through E11 coverage in mind.

Plessey at least made a 14-position turret tuner (and also an 18-position model):

Spreadbury p.151

Cheers,

Steve

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Topic starter Posted : 19/08/2019 10:27 pm
Synchrodyne
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Reputable V-Ratter Registered

As previously noted, East Germany did somewhat differently to the rest of Eastern Europe.

Its submission to ST52 included a request for several 8 MHz TV channels in Bands I and III, and also below Band III down to 144 MHz. These channels corresponded with those in the Russian submission. Thus it would appear that the initial plan was to use the Russian 625-line system with its 8 MHz channel. The actual channels proposed for use were:

40.5 to 48.5 MHz, same as Russian proposed SB1

58 to 66 MHz, same as Russian proposed SB3

144 to 152 MHz, same as Russian proposed 1

152 to 160 MHz, same as Russian proposed 2

168 to 176 MHz, same as Russian proposed 4

184 to 192 MHz, same as Russian proposed 6

192 to 200 MHz, same as Russian proposed 7

200 to 208 MHz, same as Russian proposed 8

ITU ST52 Doc 52 E Annex 1 Eastern Germany

The ST52 output provided for several Band I and Band III allocations for East Germany, these corresponding to the proposed Russian channels SB1, SB3, 6, 7, 8 and 9. Any plans that East Germany had to use channels in the 144 to 174 MHz range would not have been recorded in the ST52 output, which did not include any Eastern European out-of-band allocations.

As with Eastern Europe generally, what happened in East Germany differed from the ST52 output. But in the East German case, not only were the channel frequencies different, so was the TV system. Evidently East Germany elected to use the Western European 625-line system in a 7 MHz channel, rather than the original Russian version in an 8 MHz channel. One may surmise that this was done in order to have uniformity with West Germany.

The WW 1959 March article reported that the following 7 MHz channels were then in use in East Germany:

Channel 1: 59.25 MHz vision, 64.75 MHz sound (58 to 65 MHz)

Channel 2: 145.25 MHz vision, 150.75 MHz sound (144 to 151 MHz)

Channel 3: 55.25 MHz vision, 60.75 MHz sound (54 to 61 MHz), same as channel E3

Channel 5: 175.25 MHz vision, 180.75 MHz sound (174 to 181 MHz), same as channel E5

Channel 6: 182.25 MHz vision, 187.75 MHz sound (181 to 188 MHz), same as channel E6

Channel 8: 196.25 MHz vision, 201.75 MHz sound (195 to 202 MHz), same as channel E8

Channel 11: 217.25 MHz vision, 222.75 MHz sound (216 to 223 MHz), same as channel E11

WW 195903 p.113 East German TV Channels

The Band III channels all corresponded with Western European channels, both in number and frequency.

Channel 1 shared its vision frequency with definitive Eastern European channel O2, which corresponded with the original Russian proposed channel SB3.

Channel 2 shared its vision frequency with the original Russian proposed channel 1.

Thus the East German channelling at the time was something of a hybrid, retaining a couple of elements, namely channels 1 and 2, derived from its original ST52 proposal, but largely following Western European practice.

How long this arrangement lasted I do not know. ST61 Band I allocations for East Germany were in the standard E-system channels. However, ST61 would not have included the out-of-band channel 2 even if it were still in use. Nor did the ITU 1960 Geneva special meeting address this; it covered only the Eastern European out-of-band allocations between Bands I and II, i.e. 68 to 87.5 MHz.

Cheers

Steve

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Topic starter Posted : 19/08/2019 10:37 pm