amplifiers ("loftboxes")

[Stefan]

Another stupid question for the experts from me but I need to check my understanding before spending the euros.

I currently have a TV in the lounge fed  (via scart lead) from the sat box.  I would like to share the signal with other TVs (French born and bred)  in the house and perhaps also feed terrestrial French TV to all the sets.

As I understand it all I do is feed an amp ( in the loft?) from the RF2 output of the satbox using suitable co-ax, input from the terrestrial roof aerial as well  and then feed the whole lot back down to each set from the amp outputs'. 

I've looked at amps on the web but am a bit reluctant to buy from a UK source because of the compatability with the French TV's. I'm also now wonder if there are any problems with feeding the signal from a "UK" satellite box into a French spec Amp.?

 

Any hints, tips would be appreciated.

 

Stefan

 

 

[Martin963]

Generally you connect the (roof) aerial with coax to the RF input on the sat box.   You then take the RF out from the sat box (in this case your RF2) back up to the attic (or wherever you are putting the amp) and connect it to the input with coax.   Then you feed the amplifier output(s) with coax to whever you have the TV's.

But it doesn't always work that well, even in the UK,  particularly if the aerial signal is a bit weak.  This incoming signal may be degraded by the strong sat box output.   Judicious selection of the UHF channel used for the sat box RF output can mitigate the problem.

The problem you may have is that if your sat box is UK sourced (is it a Sky box?) it may (or will for a Sky box) output a system I RF signal.   Although the PAL part of this is OK for French TV's (which switch between PAL and SECAM pretty much by themselves as a rule) the sound offset may not suit your French TV's - unless they can be switched to system I.  Most French TV's cover systems L (the French one) and B and G;  not all will work with I.   If your satbox isn't a Sky box then you may be able to adjust its RF output to suit the TV's - if it is from Uncle Ru then it will only do system I.  You've avoided this problem up to now by using the SCART lead which carries the sound separately from the picture.

You can find out by testing each TV individually with the sat box using the RF o/p and a short length of coax before investing your dosh.

Amps seem to be quite sensitive to lightning spikes carried on the mains,  so maybe a power filter of some sort would be a good idea. 

There is no difference in terms of the amp itself between a UK sourced and a French sourced unit.  You may just run into the system problem outlined above.

[Stefan]

Martin

Many thanks for that...isn't European harmonisation, cross border standardisation etc a wonderful thing. 

[Martin963]

Well yes - harmonisation.   But then it's no good for what I believe is now known as "legacy" equipment. 

The TV systems problem is a residue from M de Gaulle's (remember him?) attempts to keep Japanese imports at bay.  In those days it was expensive to make sets that could switch from one system to another - nowadays it's almost always all contained on one chip.  So choosing - and then sticking with - SECAM colour,  AM sound,  and positive picture modulation all contributed to making non-French manufactuers think twice before trying to muscle in on the French market.

And it worked............ for years you were lucky to see a Sony TV in France......

Hope you find you can get round the problems

 

[Stefan]

Yes I think I'm suffering from exactly the "legacy equipment" problem you describe; sky box , JVC TV brought with me from the UK and of course the current French TVs. At the moment I've got as far as the roof aerial connected to the skybox - if I plug a French TV into RF2 I get picture and sound from the terrestrial signal ( I assume I now need to tune French TV to the output of the skybox - I'm guessing it should just pick it up as another channel????)

On the other hand there seems to be no way of seeing the terrestrial signal on the JVC TV, that's still sat picture, via scart lead. ......

In conclusion I think I've got all the wires in the right place but  French TV showing French terrestrial TV only, JVC main set showing satellite only........

 

[Martin963]

Not the best time to reply (after a couple of beers) but what happens if you run a coax lead from RF1 to the JVC TV,  then push the TV button on the remote (or put the Sky box in standby)?

What I suspect is happening is that the Sky box is gaining control of the TV via the SCART lead when it's turned on.   If you can get the TV back to RF mode (rather than AV) as outlined above you should then be able to ask it to do a UHF channel scan.

But you may find that if it doesn't "do" system L it won't admit to finding anything (mainly because the sync pulses on French TV are the "wrong way up".