tv distribution

[Stephen]

Hello,

I hope this counts as a DIY question; if you think it belongs in an AV/home cinema group, please let me know of the most appropriate place to post it.

I was wondering about tv distribution. At the moment I have the aerial go into a distribution amplifier in the loft, which then runs to sockets in various rooms.

I realise that composite and UHF are the worst ways to share pictures but sometimes I hear of people sending a picture from say a Sky box in their lounge along some coax to a second TV in their bedroom.

I was wondering how this works. Do you take the aerial straight down to the lounge then take a second coax back up to the loft and put that into the distribution amp. That's the only way I can think of.

However I have seen some 8+1 amplifiers and I am not sure what the "+1" means; the web sites do not make it clear. It looks as though one output has a much higher gain. Why would that be?

I read the wiki and that mentions amps in the loft and there seems to be a worry about fire risk. Should they be moved into the airing cupboard where they can be seen?

Thanks, Stephen.

[Baz]

Stephen.

Use something like this :-

$ja=tsid:11527%7Ccc:%7Cprd:5347926%7Ccat:Tv+And+Video+SendersTinyurl are others, Google "TV Sender"

Allows you to control the Sky Box from your bed.

Baz

[Jim]

You might want to try uk.tech.digital-tv (crossposted).

[The Natural Philosopher]

So you can run a passive splitter ion the end and get say 4 more outputs.

I run mine in the office, along with the PABX, the router, the print server, the file server, and the ethernet switch. Toasty.

[NT]

its not ideal, but a lot more practical than other options.

another coax from lounge box to the distribution point. A splitter to combine the 2 signals before distributing the result. The other option is a loftbox, which does this all in one.

upto you. If its convenient/practical it would be safer. 69,000 house fires per year in UK.

NT

[john]

Maybe I've read it wrong? but 'composite' (CVBS) should be a massively strong, low frequency signal of about 1V pkpk. Would way overload any TV aerial amp.

[Stephen]

Thanks. I hadn't heard of that group before. I've had a quick search for a FAQ but all I could find was a post from 2006 saying there wasn't one! What does "digital TV" include/exclude? Is it only about freeview? Does it include satellite or is that a topic for another group?

Returning to my original post, I had been looking at Antiference distribution amplifiers, whereas I think I need a loft box which is slightly more sophisticated. From what I could tell from the antiference web site, they don't make any. Do they?

I have found a Labgear HDU681 and that seems to fit the bill. The box claims to be eight way but with the downlink as well, I guess it is actually nine way? Has anyone used one and is there anything good or bad I should know about it? Is there anything better?

I don't have satellite (yet) but I see it has two satellite inputs (LNB1 and LNB2). Don't some people have quad LNBs? I'm not sure what a quad LNB does, but if I had one, presumably I would not be able to use this box as two of them could not be connected?

There is also an input for CCTV, which is something else I do not have at the moment. From the Labgear pdf I have found, it looks as though it only supports one camera though. Could you modulate two cameras on different channels and then combine their feeds into the input?

Thanks, Stephen.

[Stephen]

Yes, you did ;)

I was talking about distributing a modulated UHF signal. I was anticipating that people would say that modulated was worse than composite which is worse than scart etc. so I put in a disclaimer saying I realised that UHF and composite were the worst ways to distribute AV. The problem is that UHF and composite require less wires than S-video or scart. I wouldn't enjoy wiring a 21 way extension scart lead! The composite was a red herring, sorry for any confusion.