lets talk RF ariels and antennia

right, we got a rooftop areai in my house, that goes straight from the loft down to the TV in the front room,

how hard would it be to connect my tv in my room to that same arial ?

is it just a case of putting a splitter in there, and routing it into my room ? or is there more to it than that ?

if i do put a splitter, the downstairs TV wont lose half its signal will it ?

You can buy a splitter install it and have two separate leads to two different sets. It is true that each time you use a splitter gain is lost which effects the signal strength.

However, this is rare when installing in a normal household. You would have to be right on the limit of normal signal strength for it to make a difference. Even then, once you have installed the splitter and DO find that you have lost signal strength, you can buy small, cheap and simple gain boosters to plug in and increase the signal strength. That or you can buy a high gain aerial.

I can't remember what the maths is now for every splitter and meter of cable installed what the gain loss is, but I'm sure you will be fine.

Just make sure that you make the connections correctly. Just a slightly loose or misplaced bit of wire can make a big difference to the signal strength.

ok , cheers mnate

i got a signal booster in my room, so that doesnt bother me much, it just doesnt seem to do much boosting to my current signal.

Originally Posted by Warren

ok , cheers mnate

i got a signal booster in my room, so that doesnt bother me much, it just doesnt seem to do much boosting to my current signal.

I bet you have one of those little inside aerials haven't you They are crap unless you are REAL close to a transmitter. Because the signal is so weak in the 1st place there is not a lot for the gain booster to work with.

It's the same with people that install the main aerial in the roof and not outside. The signal will always be so much better with uninterrupted "line of sight" than having to fight through wooden joists, slate tiles, walls and the like. I'm sure that if the signal is fine for your main TV the splitter will work just fine.

Originally Posted by BigApe

I bet you have one of those little inside aerials haven't you They are crap unless you are REAL close to a transmitter. Because the signal is so weak in the 1st place there is not a lot for the gain booster to work with.

Signal to Noise ratio... the booster can't make out what's signal and what's noise, so it boosts both up, which results in the same poor signal you had before, only stronger!

Originally Posted by Filipe M.

Signal to Noise ratio... the booster can't make out what's signal and what's noise, so it boosts both up, which results in the same poor signal you had before, only stronger!

That'll be it. Qualified as an installer many years ago after leaving the Army and then realised the money was crap so didn't follow it up. Technical crap has got lost with time along with my memory.

Originally Posted by BigApe

That'll be it. Qualified as an installer many years ago after leaving the Army and then realised the money was crap so didn't follow it up. Technical crap has got lost with time along with my memory.

Since we're on the subject, IIRC cable losses in house runs (short ones, at least) are neglegible and splitters will induce a 4 dB loss for a 2-way or 8 dB for a 3-way.

So, if I got these values correct, and you start with a good signal you should be fine.

As for the signal boosters, install them as close to the antenna as possible; that way you'll make the signal stronger near the beggining of the cable run, where there's the least amount of noise. If you boost near the end of the cable run you'll be boosting both signal and the noise picked up by the cable.

Just my 3 cents (no pennies around here, sorry, so I threw another one in for exchange ratio!)

will it make a difference if both the TV's are using digital freeview boxes ?

(well, one tv downstairs is using ondigital, while the upstairs one, is actually a computer with a digital TV card in it )

ive got one of those signal booster ariels all in one jobbies,

over one side of the room i can recieve BBC and sky,
over the other, i can recieve 4,5 and some of the discovery channels.

Should be OK.

cool.

will this item here do the job ? (along with some cable oviously)