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Old 6th Jan 2009, 2:25 pm   #2
Mr Hoover
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Join Date: Jan 2007
Location: Faro, Portugal
Posts: 269
Default Re: 625-Line Television Broadcast Standards

Hi

The Uhf channel numbers I believe were assigned by the European Broadcasting Conference at Stockholm in 1961.
W.Germany commenced some Uhf transmissions possibly earlier than this,
around 1960 according to old "Practical Television" magazines.Some early
Uhf tuners there didn't have channel numbers,just a scale.

Read somewhere the 625 line system was initiated in 1946 & some
experimental transmissions from Holland started around 1948/49.

Belgium ditched the narrow bandwidth 819 line variation around 1963
& dropped system C in the late '70's.

Luxembourg also used the narrower bandwidth 819 line system on band 3
till possibly the early 1970's when it changed to system C and then
system B in the late '70's(Band 3 Channel E7 which now puts put DTT
transmissions).

France had some 819 line relays of their first network on Uhf to
otherwise system L standard (positive modulation + 6.5 MHz audio)
& not the Vhf system E standard.

The BBC were experimenting with 625 line vision with + 6.5MHz audio
in the late '50's from Crystal Palace on Uhf around what would become ch 43/44.

No doubt system N was introduced sometime in the 1950's.Brazil had TV
from 1950 so sometime after that probably.

I heard a story that Cuba which uses system M experimented with Secam
colour as they weren't keen to use the American NTSC system but the
two FM colour subcarriers used with Secam wouldn't fit happily into the
fairly limited space & no doubt caused problems with the 4.5MHz intercarrier
sound.They ended up using NTSC in the end!

Interesting article in an old Practical TV magazine of someone living in
Belgium in 1963 & the channels/systems he could receive,using a UK Ekco
export TV set & various aerials.

Hugh

Last edited by Mr Hoover; 6th Jan 2009 at 2:33 pm.
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