HD TV. circa 1950


In December 2013, an extraordinary collection of early technologies went under
the hammer at Bonhams in London. Among the treasure trove was a working
Teleavia type P111 television set from 1950. Designed by Citroen DS designer
Flaminio Bertroni, the odd-looking set is one of the earliest examples of high-
definition TV. High-def from the 1950s?

The invention of the television cannot be attributed to one man; it was a slow
process of collective improvement between researchers from different countries
and tinkerers whose initial concepts date back to the 1880s. It was the
successive discoveries in electricity and electronics that helped to achieve the
theoretical projects of the first researchers.

Enter Rene Barthelemy, a brilliant French engineer responsible for numerous
impressive electronic achievements in the broadcasting field through the “20s
and “30s including developments of the Nipkow lens disc and research into
adopting a worldwide standard for transmission.

As head of French Television, Barthelemy initiated regular broadcasts, using the
Eiffel Tower as a transmission mast with a power of 10 kilowatts, on 4 January,
1937, in 180 lines of definition. In July 1938, a three-year decree defined a
standard of 455 lines VHF. In 1939, broadcasts continued despite there being
only 200 to 300 individual television sets in Paris. With the entry of France into
World War II the same year, broadcasts ceased and the transmitter of the Eiffel
Tower was sabotaged.

During the war years Barthelemy, now a member of the Academy of Sciences,
continued to work effectively in the field of television, using his inventive genius
and rigour to develop a 1015-and 1042-line system before settling on a more
stable 819-line structure.

When Europe resumed TV transmissions after WWII (ie. in the late 1940s and
early 1950s) most countries standardised on a 576i (625-line) television system.
On 20 November 1948, François Mitterran, (the then Secretary of State for
Information), decreed a French broadcast standard of 819 lines; broadcasting
began at the end of 1949 in this definition. France was the only European
country to adopt it.

This was arguably the world’s first high-definition television system and by
today’s standards it could be called 755i (as it had 755-lines active) with a
maximum theoretical resolution of 408×368-line pairs (which in digital terms can
be expressed as equivalent to 816×737 pixels), with a 4:3 aspect ratio.

By comparison, the modern 720p standard is 1280×720 pixels, of which the 4:3
portion would be 960×720 pixels. The choice of number of lines has to do with
frequency divider circuits. Before the advent of ICs you could only do odd
numbers (usually primes like 3, 5 and 7) of divisions of a main clock frequency to
obtain the line and field rates. With a mains power frequency of 50Hz the values
of 13 x 7 x 3 x 3 give 819 lines.

The development of a high definition standard was an impressive achievement, –
but, was France and its overseas territory markets large enough to sustain the
format in the face of a globally developing broadcast industry with its cheaper
sets on the consumer side and broadcast equipment on the technical side? The
signal also took up a relatively whopping 14mHz, double the amount of 625 line
systems, meaning that fewer channels were possible, plus there was the small
matter of colour.

Despite some attempts to create a colour SECAM version of the 819-line system,
France later abandoned it in favour of the Europe-wide standard of 625 lines
(576i50), with the final 819-line monochrome transmissions from Paris in 1984.
TMC in Monaco were the last broadcasters to transmit 819-line television, closing
down their System E transmitter in 1985.

What makes the Teleavia type P111 television set unique is that it was a ’dual
standard” TV, with the capability to show 441 lines along with a high definition
facility of 819 lines. It is speculated that Teleavia may have been trying to
’future-proof” the P111 in case the French government decided to change their
minds and standardise with their European colleagues earlier than they did.


Please enter your comment!
Please enter your name here