New Aerial Problems

[m4tt]

I have just installed a new aerial in the loft and I am having some difficulties, hope someone can help. It all worked fine previously with the roof mounted set-up.

I can get all channels on one TV which is upstairs and has new coax cable. The TV downstairs I can't get all of the channels, which is using the old coax cable in the walls. Both TVs are very similar so would expect similar results. Is there some kind of amplifier I can buy to make it all work? Don't want to replace the cable down the wall as it will be difficult.

Any speedy help appreciated!

[cjs]

Are you using the same loft aerial for both TV's? If so how are you splitting the cable?

[m4tt]

Just a cable split adaptor, nothing special. Even if you take it out the equation it still doesn't work properly.

[cjs]

Then you have a poor signal that degrades over the longer cable distance or, the cable downstairs is bad or, the connections on then cable downstairs are bad. Check the connections.

Depending on your location, aerials should not be in the loft if you're trying to get Freeview, has the analogue TV been switched off in your area yet?

You can get a two way distribution amp for £10 ish, you will need a power socket in the loft for it.

Also note that different Tv's or Freeview boxes have different tuner sensitivity, one will work where another wont on the same cable feed. Again a good signal is required.

Edited by cjs on Tuesday 2nd November 08:58

[Toffer]

The splitter (if it is a good one), will reduce the aerial signal by 3.5dB on each drop coaxial cable. This means that with et loss incurred by connectors and cable, you will have much less than half the signal received at the aerial, at the TV wall socket.

I am sorry to tell you, that unless you are in a very strong signal area, loft aerials are really not very good when compared to roof installations (the roof screens (attenuates) the signal and you have a lower reception point). The other thing you did not mention, is that I assume you had a roof mounted analogue TV aerial and have installed a loft digital TV aerial? This is making matters even worse because the digital TV transmission levels are generally lower than those for analogue off-air TV.

I suggest you buy a high gain roof mounted digital TV aerial (suitable for your area...a good installer will know this) and be ready to replace old coaxial cable with new. The bamboo 75 ohm cable often suffers with moisture ingress which corrodes the cable and of course also changes its impedance.

If the high gain aerial and new cable does not do the job, then buy a decent aerial drop amplifier. You should get one that is powered from a mains (240VAC to DC) transformer, with a power inserter on the aerial cable (your installer will know of a good one).

Probably a good place to start is the CAI website...

[Daniel1]

Buy a cheap splitter type amplifier from maplin or argos and try that.As your getting all the channels on one tele but not on the one with the old cable you may be lucky enough that the amplifier will over come the loss and it may work.

If it doesnt, get an aerial guy in.

[m4tt]

Thanks for all the replies. I did have a roof mounted aerial, but having fascias and sofits replaced and they took it down for a couple of days. So I thought I could do away with the roof aerial and try a loft one. Alas it hasn't worked and without some reasonable effort and expense doesn't seem like it will work. So will just go back to the old aerial which worked fine.

Thanks for the help once again.