Further TV aerial socket - distribution amp required?

[Geejay]

Hi

I'd be grateful for some advice on a hopefully straightforward situation.

I have a roof aerial with excellent reception - I live within sight of the Winter Hill transmitter. I'm currently feeding two TVs off it - living room & kitchen. I'm looking to put in one more feed to the main bedroom.

If I can avoid it I'm not inclined to go down the loft box/distribution amp route as I doubt I'll ever be wanting any more than three aerial points. Preferably all I want is another feed straight off the aerial, down the side of the house and in through the bedroom wall.

My question is - do you think the aerial will be able to take this without any loss in quality? I know ultimately it will depend on individual circumstances but a rough idea would be useful as I'm pretty clueless!

I'll be getting someone in to do it for me, but I haven't got any personal recommendations so I'll just be picking out of the local classifieds. What I don't want is for someone to suck his teeth, mutter about signal loss and try and flog me a distribution amp system when it might not be needed!

Is there anything I should watch out for or questions I should be asking? What sort of quote should I be looking at?

Any advice gratefully received!

Thanks in advance.

 

[Diyisfun]

To try it why not just buy a Y spitter for a few ££, try it if the reception is ok, then get it done properly.

 

[cyndi]

well in reality you cannot really just connect three lenghts of coax to one aerial

as this will affect the impendace seen at the aerial ,aerial coax is 50ohms so connecting three bits to one would give an impedance mismatch ,
for the sake of a 20-40pounds buy your self a 4way amp from some one like "tvlink" your going to need three ouputs anyway.then feed one piece of coax to amp then three to the locations.
you say you have a roof aerial with excellent reception already so no real need to get some one in to add an amp very easy to do

aerial ---coax---amp in --- oultet 1 --coax --tvlounge
outlet 2 --coax---kitchen
outlet 3 --coax--bedroom

 

[Diyisfun]

If you a vcr take aerial into vcr then to the amp, you can then watch vcr on the other tv's

 

[bernardgreen]

The impedance of terrestrial TV signal aerial systems is 75 ohm

In a strong signal area with good aerial 3 TV's could be run using "Y" splitters


---------Y----------- TV1 ( has best signal )
. . . . . . .\-------Y----TV2
. . . . . . . . . . . . \---- TV3

(ignore the dots)

Resistive splitter lose signal but are cheaper to test out whether there is enough signal. If the pictures are tolerable then upgrade to inductive ( transformer ) splitters which have less loss than resistive splitters.

With any Y split system an open ended lead ( not plugged into the TV ) can cause "ghosts" to appear on other analogue TV sets. ( signal reflected back from the open end creates a delayed 2nd image to appear on other sets ).

 

[Geejay]

Thanks for all the advice.

I think for now I'm just going to try a 3 way splitter and see what happens. If the quality deteriorates then I'll go down the amp route. I don't fancy doing it myself (Rod Hull!) so I've got a chap coming in on Friday who'll do it for £35. Seems reasonable and he's got a good local reputation, so hopefully be ok.

 

[Kingston12]

I have heard that the roof mounted amp is always the best route if you can do it.

Having said that, I bought a cheap 3 way splitter (£10-£15 at Maplin), and it feeds three TVs in different rooms with no discernible qulaity loss.

 

[cyndi]

The impedance of terrestrial TV signal aerial systems is 75 ohm

In a strong signal area with good aerial 3 TV's could be run using "Y" splitters


---------Y----------- TV1 ( has best signal )
. . . . . . .\-------Y----TV2
. . . . . . . . . . . . \---- TV3

(ignore the dots)

Resistive splitter lose signal but are cheaper to test out whether there is enough signal. If the pictures are tolerable then upgrade to inductive ( transformer ) splitters which have less loss than resistive splitters.

With any Y split system an open ended lead ( not plugged into the TV ) can cause "ghosts" to appear on other analogue TV sets. ( signal reflected back from the open end creates a delayed 2nd image to appear on other sets ).

well most y splitters have a 3db loss across them so your tv3 would have a 9db loss ,every 3db is half the signal

thanks for the 75ohm point - your right -have been doing 50ohm ham stuff last few days