poor tv reception - connection of RTE and BBC

[rich2000]

Hi folks having a problem with my tv reception.

Originally had just an aerial on the roof picking up BBC but wanted to pick up RTE also so installed another aerial in the roofspace.

I then cut the original coaxial cable and put it through a diplexer along with the coaxial cable from the other aerial for RTE which has a booster attached.

However there was no picture for any RTE channels but BBC was still very sharp. I then tried changing the positions of the BBC cable and RTE cable in the dipelxer. However picture became poor on all chanels.

The strange thing is now my picture on BBC is now poor - can anyone suggest what could have happened as the picture remains poor even with the BBC cable connected to TV and there has been no movement of my BBC aerial?

hope someone can help

thanks

Richard

[ericmark]

When connecting two aerials able to receive the same signal they must be phased in. The length of coaxial cable between the two aerials is critical. One can for example use 9 yargi beams together as radio hams do when bouncing VHF signals off the moon but setting them up is not easy. Here we can receive Winter Hill, Central, or Moel-y-parc and either a rotator on a single aerial or a switch is required we do not connect them together. Sky, UHF, DAB, and VHF may be able to work together but these are different frequencies and at the wall band pass filters re-split the signals. I think about 60cm is a wave length if you want to play you can try altering cable lengths but I would not recommend it.