 |
UK Broadcast Transmission |
         |
|
    |
|
|
|
|
|||||||||
|
|||||||||||
CHANNEL 5
THE TEST TRANSMISSIONS
The UK's fifth terrestrial television station began broadcasting on Easter Sunday, 30-Mar-97.
Test transmissions began in some areas from 2-Jan-97, though brief engineering tests were conducted at some sites in late '96.
Until 19-Feb-97 details of these test transmissions could be found on CEEFAX P698. Unfortunately the BBC later withdrew this valuable resource, which was a pity as it was one of the few sources of useful information we had.
Getting any kind of accurate information out of Channel 5 Broadcasting themselves was very difficult and I received a number of stories of apparent mis-information being put out by Ch5, both to the public and to their own retuners. For example, there had been persistent rumours about the test transmissions being on reduced power... At least one retuner was told this by Ch5 and this seemed to be one of Ch5's stock methods of deflecting criticism.
There was, however, a short period of deliberate reduced power working from EMLEY MOOR in South Yorks. which I understand was to test how certain elements of the NTL transmission system reacted to fault conditions. I also detected short periods of reduced power from Croydon, possibly for the same reason.
|
This is what was first seen from the CROYDON transmitter from 0900-2000 on Sunday 26-Jan-97. The caption was locally generated at Croydon. There was no teletext or NICAM sound and the analogue sound consisted of a continuous tone |
 |
And this was the reaction! I must admit, I'm still intrigued... what were the other 33,000 suffering from?! |
 |
|
This is what we saw from 0945-2000 on Sunday 2-Feb-97. This caption was distributed via the Orion satellite MPEG digital feed and the NICAM and analogue sound consisted of a continually repeated announcement... Ch5 were already making use of their 'regional' capability, most transmitters put out a caption with the telephone number ending ...327, but Croydon maintained the ...328 number until 24-Mar-97 |
 |
By the final week of test transmissions all transmitters were receiving teletext. (And BTW, that's not how you spell Cambret.) |
 |
From 24-Feb-97 Channel 5 changed their 'colour bars' again to look like this... ... and the test transmissions then consisted of a ten minute sequence, the first 6'30" of the 'colour bars' caption... |
 |
... followed by a 3'30" promo video. The ten minute sequence then repeated... |
 |
Tuesday 25 March, we got a shorter (8' 00") video sequence which included a longer promo, a caption with amended phone numbers... ...and this appeared on teletext P500: (Try saying it 5 times, quickly, after 5 pints!) |
 |
Shortly after that the
header row was changed to something rather less informative. |
 |
An hour before launch at
1700 (5pm!) Channel 5 showed this countdown clock, accompanied by a ticking sound. |
 Many thanks to Darren Meldrum for the screen captures. He has more at the Meldrum Home Page. |
There was a further short period of Channel 5 test transmissions on Astra transponder 63 (10.92075GHz horizontal) between about 0700 21 April - 1300 23 April 1997. These tests consisted of a similar promo video to the one used for the terrestrial tests, with the additional benefit of the Spice girls video! The Astra tests were transmitted without encryption, although Videocrypt 1 was used for the programme transmissions.
During summer '97 Channel 5 added ten further transmitters to its terrestrial network. Once again initial tests were locally generated and consisted of the familiar colour bar caption and tone, with no NICAM or teletext signals. Subsequent tests consisted of a programme feed with a superimposed caption. A full screen caption was also shown in place of commercial breaks. Channel 5 used one of their four virtual regions to supply this modified programme feed.
Some viewers noticed a problem with the NICAM audio of this feed, commenting that the sound had too much bass. Following up on these reports I contacted Channel 5 who promptly rectified the fault.
Channel 5 index | Channel 5 transmitters
|
|
|
||||||
|
