Why have I lost all things Channel 7

[Seymour Butts]

I have a Fusion HDTV card installed in my PC. Up until a few weeks ago all seemed fine, all channels came in with no problems and whilst the card displays the signal quality I had never really taken any notice.
But over the last couple of weeks the signal has degenerated so much that the 7 suite of channels are now almost unwatchable.
Here are some examples;

Channel 1 Digital: 99% 24.0db - Great Picture
Channel 7 Digital: 70% 16.9db - Crap or NO picture
Channel 72 Two 68% 16.5db - Crap or NO picture
Channel 73 Mate 68% 16.5db - Crap or NO picture
Channel 9 Digital: 90% 22.3db - Great Picture
Channel 10 Digital: 90% 24.1db - Great Picture
Channel 11 Digital: 98% 24.3db - Great Picture
Channel 90 Gem: 99% 24.0db - Great Picture
Channel 99 Gem: 99% 22.0db - Great Picture

Do I assume that my Antenna has moved or is Channel seven playing silly buggers with their transmissions??

[Seymour Butts]

Decided to look deeper - Feken dodgy cables - All pics back

[gordon_s1942]

deleted as posted as problem was sorted................makes you wonder why the problem only affected one 'suite' and not all.

[donhe7]

deleted as posted as problem was sorted................makes you wonder why the problem only affected one 'suite' and not all.

I'll agree with that, I have the same situation, with a system using some old foam insulated, "tinfoil" shielded cable, but in my case, Channel 7 rubbish at times, but on changing to 7two signal clears. I may get around to fixing it, (not important at this point in time)

donhe7

[gordon_s1942]

If its an old installation then its obvious when you do replace the cables you get the quad shield RG6 and replace any connectors as well.
Depending on the age of the antenna, that's worth considering replacing too because some arent that well built and have poor cable connections along with the changes coming to the bands and frequency's over the next 18 months.

[donhe7]

The particular system is a home-built quad bow tie, copied from a design in "Silicon Chip", but with modification to measurements to bring the frequency toward the lower part of the UHF band, an experiment which seems to have worked, for the last ten years or more, until the advent of digital reception.
The active elements of the aerial were made from "tinned" brass and copper, as well as the "harness", as we are in an area with a certain amount of salt air, so this was a consideration at the time of construction

donhe7