1956 BBC Colour with an RCA TK-41

[Penthode]

Here is an interesting clip I found from a 1956 BBC Panorama programme which includes a depiction of BBC colour television tests from Studio A at Alexandria Palace. Note the RCA TK41.

"Panorama", the longest running current affairs programme on television, is still running on BBC1 in the UK. Richard Dimbleby, the host, describes behind the scenes at BBC television. The colour tests in 1956 followed the 405 line NTSC standard: the UK eventually adopted 625 line PAL in 1967.

https://www.youtube.com/watch?v=2G36AaMDFdM

[NewVista]

Marconi camera in style of RCA?

[colorfixer]

More likely EMI "built" cameras "under license". They probably "sourced specific components" from RCA - like the housings, tubes, bodies...

[ppppenguin]

These colour cameras were built by Marconi, not EMI. They used 3 image orthicon tubes. Due to their size and shape they were colloquially known as "coffin cameras". I don't know how much RCA technology was used. At one level they were just 3 monochrome cameras in the same box. This ignores the colour splitter block and the difficulties of registering the 3 images.

[old_tv_nut]

Originally Posted by ppppenguin

These colour cameras were built by Marconi, not EMI. They used 3 image orthicon tubes. Due to their size and shape they were colloquially known as "coffin cameras". I don't know how much RCA technology was used. At one level they were just 3 monochrome cameras in the same box. This ignores the colour splitter block and the difficulties of registering the 3 images.

They look essentially identical to the RCA, including the way the IO assembly swings out, the tapered width of the sides, etc. So yes, assembled by Marconi, with a heaping help of drawings and parts from RCA, most likely.

[Edit: can't review the video here at work - did I remember the tapered shape of the cabinet correctly? - If not tapered, would indicate that Marconi built the cabinet.)

[colorfixer]

EMI was highly incestuous with RCA, I presume that Marconi was also probably in bed with them as well. RCA did evolve from Marconi's attempt to setup shop in the U.S.A..

[ppppenguin]

The relationships between EMI, RCA and Marconi were complex and varied. For example in the 1930s when Marconi and EMI formed a joint company to develop TV in the UK Marconi's association with RCA gave access to RCA's patents including, notably, Ballard's on interlace.

The question of interlace is actually controversial since it was hardly novel at the time of Ballard's patent. Baird had pioneered what he called "intercalation", inculding hihger order interlace and Sanabria also did interlace long before Ballard. See this Videokarma archive thread: http://www.videokarma.org/archive/in.../t-251513.html

[Penthode]

I know that a number of RCA cameras eg TK10/30 were licensed for manufacture by Marconi until they went on their on. However, because colour was new and considerable development went into the cameras and also because the BBC were conducting initial tests, I believe the cameras depicted were imported and modified by the BBC for 405 line NTSC.

Is their ant evidence Marconi built these cameras for the 1956 tests?

[ceebee23]

It is a pity that ITV did not get its way on NTSC 405 line ... the Beeb seems to have not wanted to proceed because colour 405 would reduce the pressure for the switch 625 line and as result a decade of UK broadcasting is only b/w

[Steve D.]

BBC article on color TV experiments in the 50's. Article courtesy of the ETF site:
http://www.bbceng.info/Technical%20R..._colour_tv.htm

-Steve D.

[ppppenguin]

http://www.tvcameramuseum.org/marcon...olour/p-1.html

[ceebee23]

About half way down the page is a description of a Ekco CT100M ... one of the sets built to test the possible 405 NTSC standard...


http://www.oldtechnology.net/colour4.html

and the picture is here
http://www.oldtechnology.net/images/ekcoct100m.jpg