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January 1967 Radio-Electronics
 [Table of Contents]
Wax nostalgic about and learn from the history of early electronics.
See articles from Radio-Electronics,
published 1930-1988. All copyrights hereby acknowledged.
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 It is kind of hard to believe that even by
1966, when the International Telecommunications Union (ITU) met in Oslo, Norway,
that the world had not yet agreed in a common transmission standard for color
television. In January of 1967, Radio-Electronics magazine editor Thomas Hasket
interviewed two major players in the industry, George Brown of Radio
Corporation of America (RCA), and Frederick M. Remley, Jr. of Society of Motion
Picture and Television Engineers (SMPTE), regarding the stalemate that was
unarguably hampering the ramping up of color television set production.
Consumers were pining for them, but companies hesitated to invest engineering
and manufacturing resources when they couldn't be sure it would not be thwarted
by a change in the modulation scheme. A battle was being waged between the U.S.
NTSC
standard and the European PAL system (and
SÉCAM to a lesser sense). Both
had strengths and weaknesses, but history has shown, NTSC ultimately won.
Possibly due to the impasse, color TV sales in America did not surpass B&W sales
until the early 1970s.
What Happened at Oslo?
George H. Brown of RCA (left), and Frederick M. Remley, Jr. of
SMPTE (right).
Why there isn't worldwide agreement on a color-television system.
By Thomas R. Haskett
Previous Radio-Electronics articles have discussed color television as proposed
throughout the world.* This subject was one of several considered by participants
in a conference at Oslo, Norway, during June and July 1966. To find out exactly
what was discussed, why it was discussed, and why the conference ended the way it
did (Radio-Electronics, October 1966, p. 4), we interviewed two US delegates.
Dr. George H. Brown is executive vice president, research and engineering, of
the Radio Corporation of America. Long a radio and television engineer, he is the
developer of the turnstile antenna, the most widely used television transmitting
antenna.
Mr. Frederick M. Remley, Jr. is chairman of the Video Tape Recording Committee,
Society of Motion Picture and Television Engineers, and technical director of the
University of Michigan's Broadcasting Service.
Table I - Color-System Preferences by Country
Radio-Electronics: Gentlemen, would you tell us how the Oslo
conference came about?
Dr. Brown: From time to time, the member countries of the United
Nations wish to discuss matters in the areas of radio, television and communications.
Routine specialized topics are rarely discussed in the General Assembly, but usually
handled by the UN agency responsible for such affairs. The particular agency for
radio, television and communications is known as the ITU - International Telecommunications
Union.
R-E: Then the ITU sponsored the Oslo conference?
Definitions
ART: Additional Reference Transmission
CCIR: International Radio Consultative Committee (UN)
NIR: National Research Institute (USSR)
NTSC: National Television System Committee (US)
OIRT: International Radio and Television Organization (USSR and satellites)
PAL: Phase Alternation Line
SECAM: Sequential by Memory
Mr. Remley: Not directly. ITU is a large organization, involved
in many fields of international communications. One of ITU's divisions is known
as the CCIR, from the French-language initials for International Radio Consultative
Committee. The Oslo conference was the eleventh fully attended assembly of the CCIR.
A previous meeting of a portion of CCIR at Vienna set part of the agenda for Oslo,
and the discussion of a single worldwide color-television system was scheduled.
R-E: How many delegates to this color-television conference
were there?
Dr. Brown: There were nearly 800 delegates to the conference,
but color television was only one of the subjects discussed. You see, CCIR consists
of 14 study groups, which are concerned with all forms of radio communications,
their standards and definitions, and so on. Study Group XI is concerned with television,
and color was formally discussed at the meetings of this group.
C. Hoyt Price, of the State Department, was head of the US delegation to the
full CCIR conference. Arthur Hall, of Bell Laboratories was spokesman for the US
in Study Group XI, to which I was a delegate representing industry. There were some
12 or 15 other delegates to SG XI from the US, by the way, including people from
the FCC.
Mr. Remley: I participated primarily in Study Group X, where
we were concerned with things like television film standards, for example. However,
I attended some meetings of Study Group XI, and my own group discussed color-television
problems, but we took no official action.
R-E: How was the question of a universal color-television standard
brought up?
Dr. Brown: First, let me say there's quite a difference between
a standard and a system. A standard is a rule or definition, established by government
or industry, which everyone uses. A good example is the US standard of 525 horizontal
lines in a complete television frame or picture. A system, on the other hand, is
a method or means of accomplishing some goal. NTSC and SECAM are two different color-television
systems; both can be used with 525-line standards, as well as with other standards.
At the beginning of the Oslo conference, Study Group XI Chairman Erik Esping,
of Sweden, asked two questions of the delegates: "When do you expect to start color-television
broadcasting in your country?" and "What system or systems do you prefer?" The chairman
then asked for "expressions of opinions," not votes. These expressions showed that
the various countries favored a total of 4 systems. [See Table I. -Editor] It was
asked if there should be a single world-wide system, and if so, which one? Well,
it was obvious that with such a large group - about half the 800 delegates to the
entire conference - very little could be accomplished toward arriving at some sort
of agreement. The group was just too large and unwieldy. The chairman recognized
this, and adjourned the meeting for several days after suggesting discreetly that
some "cloakroom bargaining" occur before another meeting.
R-E: Could you explain where the various systems were developed
and what differences exist between them?
Mr. Remley: SECAM III is a French development, like its earlier
and now-obsolete predecessors SECAM I and II. SECAM III seems inherently inferior
to the other systems. It uses an FM sub carrier which is always present and causes
interference in some pictures, depending on scene composition. The overall picture
quality is often relatively poor. The system requires a complicated receiver, which
would probably be more expensive to manufacture than receivers for the other systems.
SECAM III's advantages are that it can be recorded easily by ordinary monochrome
video tape machines and can be transmitted by limited-performance cable and microwave
systems.
SECAM IV is the French name for the same system the Russians call NIR. Both countries
shared development of the system, and have agreed to share credit. SECAM IV has
never been field-tested. It looks good on paper, and should be easily handled by
video tape, cable and microwave. We don't know for certain what receiver requirements
are.
Dr. Brown: A great deal has been said of the ability of PAL
and SECAM to overcome differential phase errors. It was fully proven in 1965 that
SECAM worked a benefit in the presence of differential phase, and SECAM did not
suffer too much from circuit noise. But, in the presence of both noise and differential
phase, SECAM failed miserably. Furthermore, NTSC has been transmitted over a thousand
miles on the Russian microwave system, from Moscow to many cities in Western Europe,
and from Rome to London. The NTSC signal suffered very little degradation in these
test transmissions. The French attempted the same feat with SECAM and didn't make
it.
PAL is a West German development, and at least it works, which is more than you
can say for SECAM. Its primary advantage is its transmission quality, which is excellent.
It can be handled well by limited-performance cable and microwave facilities, as
well as video recorders.
The Germans want to use full PAL all the way from the camera to the receiver,
which isn't necessary. Besides, using full PAL makes the receiver more costly than
it needs to be, and is PAL's major defect. We estimate that a PAL receiver, produced
in the US, would cost the consumer $40 to $50 more than an NTSC model.
The Germans claim that PAL alleviates ghosting and multipath distortion - which
it does. But they make a big thing out of this feature, while we in the US know
that, with few exceptions, a good antenna takes care of ghosting. PAL wasn't developed
to avoid multipath - it was developed to overcome transmission problems.
R-E: What transmission problems?
Table II - World Television Standards
Mr. Remley: Most European cable and microwave transmission facilities
have been built without enough phase and amplitude linearity to handle NTSC color.
To use NTSC in Europe would mean either rebuilding many intercity transmission channels
or not using networks. It's too bad this is so, for I think that unofficially many
delegates felt NTSC was the best system, technically.
Unfortunately, although simple to manufacture, simple PAL receivers have at least
one serious defect - line crawl. Full PAL avoids this defect. The latest version
of full PAL, by the way, while supposedly good on video tape, raises new problems.
PAL gates the fields 1-2-3-4, unlike NTSC, and keeping track of the fields could
be a problem, and might entail a more complicated tape machine.
R-E: Was ART proposed?
Mr. Remley: ART, for Additional Reference Transmission, is really
NTSC with additions. [ART may also be used with PAL. -Editor] Its development is
still incomplete, as work was done and papers filed almost simultaneously by both
British and West German researchers. While never considered formally at either Vienna
or Oslo, it was unofficially proposed by some as a simpler, cheaper alternate to
PAL.
R-E: Was NTSC proposed, and did it have any chance at Oslo?
Dr. Brown: Yes, the US position favored NTSC. We have used it
here since 1953: Japan uses it, and Canada started using it last September. There
are at least ten million NTSC receivers in use in the US alone, to say nothing of
Japan and Canada. Compare this with possibly a few hundred experimental PAL and
SECAM receivers. We've had time to work the bugs out of NTSC, and I don't think
anyone contests the fact that it looks very good today.
American industry has spent a lot of money developing NTSC color, and the American
people have a lot of money invested in it. It would be foolish to scrap all that
- which is why the US won't change our system. The British agreed with us until
we got to Oslo. No, I'm afraid NTSC didn't have much of a chance at Oslo.
R-E: Why not?
Dr. Brown: Well, at one point, the chairman of Study Group XI asked: "Are you
in favor of a single system of color? If so, are you authorized by your government
to change your vote?"
The Germans answered that they could change their vote, but only after returning
to West Germany and consulting with 5 or 10 agencies and committees, which would
take nearly a year. The British said substantially the same thing. The French said
they had the freedom to vote for either SECAM III or SECAM TV. The Belgians were
very confusing in their answer.
R-E: In other words, in spite of NTSC's obvious technical advantages,
except for European cable and microwave problems, the delegates would not favor
NTSC, nor any other single system. Why do you suppose this happened?
Dr. Brown: Each country's decision to favor a certain color
system was political, not technical. For instance, PAL is supported by West Germany,
Great Britain and several other European countries. It may become a European standard.
But Russia will never adopt a German system, because of the deep anti-German feeling
that still exists from World War II. Similarly, France refuses to consider PAL because
of the pride they feel in their SECAM.
R-E: Were engineering features of the various systems considered
at all?
Mr. Remley: Engineering features were the ostensible reasons
for favoring one system over another. As mentioned earlier, European transmission
circuits make NTSC transmission more difficult there at present. And PAL is touted
as a great cure for ghosting. But underlying the technical reasons were political
motives.
R-E: What about the possibility of a compromise?
Dr. Brown: The French made a suggestion to that effect, but
it wasn't much of a compromise. They proposed that all member countries stop their
present research on NTSC, PAL and any other systems, and pool their resources for
one year to perfect SECAM IV. If at the end of one year, SECAM IV proved to be a
good system, it would be adopted as the worldwide system. If SECAM IV didn't work
out, we would then be forced, by the terms of the compromise, to adopt SECAM III
as the system. France's proposal, I'm afraid, didn't get very far.
R-E: Was any position taken by Study Group XI on a color system
for the world, or for Europe?
Dr. Brown: No. The only result was that, after a couple of weeks
of the delegates' doing nothing, Chairman Esping appointed a small group to write
a report. This report outlined the engineering features of the systems that had
been proposed. No single system was recommended or adopted by Study Group XI.
Mr. Remley: It was unfortunate, I think, that there was no agreement.
I believe the various nations of the world are playing ostrich; many have too little
concern about seeing what's going on outside their own countries - and I include
the US in this statement. Think of what a tremendous advantage a single world-wide
system and standard of both monochrome and color television would be! With satellite
relays and possibly direct satellite-to-home telecasting, a single system and standard
would permit instant communication between all nations.
Such events as the Olympic Games, President Kennedy's or Winston Churchill's
funeral, Queen Elizabeth's coronation, could be shown live to the entire world.
A single pooled camera crew could handle the origination. At the present time, such
an event requires a completely separate camera crew, with tons of equipment, for
each system in use. Of course, you can use film, which is playable equally well
on all systems, but you lose immediacy.
Dr. Brown: It would be nice to have a single worldwide system,
but I don't think it's possible - at least not through the UN. You've got to remember
that most actions of the UN are basically unenforceable. Even if a decision is reached,
it's subject to voluntary compliance by member nations. What do you do if several
countries decide not to cooperate?
R-E: Several monochrome systems are presently in use in the
world [see Table II -Editor]. The British have used 405 lines for some time, and
the French, 819 lines. Most of the rest of Europe uses 625 lines. Recently both
Great Britain and France started supplementary 625-line services, while maintaining
their other facilities. Do you think this heralds a single European monochrome standard?
Dr. Brown: Well, there was general agreement of Study Group
XI several years ago that when anyone went to color in Europe they'd do it with
625 lines. You must remember that 625 lines is the 50-field equivalent of the US
525 lines, which is of course on 60 fields. There are some differences between British,
French and other European 625-line systems, but these could well be ironed out and
we might see a single European standard.
Mr. Remley: Speaking of 50-field standards, which are used in
Europe because of 50-Hz power lines, the use of 50 fields and 25 frames causes noticeable
flicker as compared with our system, which uses 60 fields and 30 frames.
R-E: At present, what facilities exist to allow, say, British
audiences to view a live US telecast?
Mr. Remley: Standards converters are used. The US networks have
them - at least in New York City - and the BBC and others have them in Europe. They
are complicated, expensive, and may reduce definition. There are two types - electronic
and optical. When the frame rates of the two systems are identical, it's possible
to use an electronic converter, which gives the better picture.
R-E: To summarize, then: The UN-sponsored Oslo CCIR conference
did not result in a decision to adopt a single world system of color television.
It did show, however, that the various countries grouped themselves around three
systems-NTSC, PAL and SECAM. These groupings seem to be political, and the technical
advantages and disadvantages of the three systems were not the main reasons for
the groupings.
* "Color Television Throughout the World," January 1965; "The Case for NTSC in
Europe," March 1965; "Color Television Systems: Which Way Will Europe Go?" July
1966.
Posted March 22, 2023
Color and Monochrome (B&W) Television
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