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silentC
8th October 2007, 03:25 PM
We have an Austar satellite box in our lounge room and I want to set it up so the kids can watch the Austar channels on their TV, which is about 18 metres away.

The Austar box has an RF out, so I ran a cable from it to their TV but there is a bit of disturbance in the picture. If I plug the roof antennae into the RF in on the Austar box, the satellite picture is completely fuzzed out and I get one of the free to air channels coming in over the top. I suspect this may be due to the HDTV signal.

I've thought about taking the audio/video out and routing it to their TV but that means I'd need another 40 metres of coax.

Any suggestions on how to improve the signal from the RF out? Is there a filter I can get, or is it worth trying an amplifier or something?

Separate but unrelated question: Does anyone know what the difference is between a 2 way splitter and a 1 way tap?

chrisp
8th October 2007, 03:49 PM
Separate but unrelated question: Does anyone know what the difference is between a 2 way splitter and a 1 way tap?

silentC,

I'm not familiar with the Austar gear so I'll leave that to someone who does know rather than provide some silly guess :rolleyes:.

With regard to your supplementary question, a splitter splits the signal equally between the outputs. In the case of a two-way splitter about 1/2 the signal to each outlet. A tap is designed for large distribution systems (such as used in a motel) where you only want a small amount of the signal to go out the tap (and most to continue on down the line to further taps).

silentC
8th October 2007, 03:57 PM
OK, makes sense, thanks. What I've done is moved the TV in their room to an opposite wall, so I want to tap into the cable running down to the old TV point and run a new one to the new position. So I guess a 2 way splitter is the way to go.

chrisp
8th October 2007, 03:59 PM
OK, makes sense, thanks. What I've done is moved the TV in their room to an opposite wall, so I want to tap into the cable running down to the old TV point and run a new one to the new position. So I guess a 2 way splitter is the way to go.

aye

rrich
8th October 2007, 04:45 PM
Separate but unrelated question: Does anyone know what the difference is between a 2 way splitter and a 1 way tap?


Usually a 2 way spliter is a bi-directional device. This allows the set top box to talk to the service provider. This reverse channel would be used for STB validation, pay per view charging and subscription channel enablement. I'm not sure what the 1 way tap is.

If your satellite works like ours, I don't think that you can accomplish what you are attempting. What happens is that the signal comes into the STB as a wide band signal with each channel in its own part of the spectrum. Then the STB decodes, isolates and converts the selected channel to HDTV (on your main set). For the kids to watch, they will need a STB of their own and you may need a dual channel wide band amplifier on the satellite dish.

Think of it like an old coax LAN. Everything goes by but the NIC in your computer extracts and decodes traffic intended for your computer.

silentC
8th October 2007, 04:54 PM
Sorry Rich, the 2-way splitter I'm referring to is simply to allow you to feed the one signal to two different points - in this case I have a cable from my free-to-air antennae and I want to split it off to two wall sockets (only one will be used). It's nothing to do with the satellite in this case.

We did have two satellite decoders here but got rid of one because of the cost. What I want to do is take the RF out from the decoder, which would normally go to your TV, and basically run it to a TV in another room with a 20m long extension. The RF signal is already decoded from the satellite.

These decoders have a number of outputs that can be used to connect to your TV, the main two are RF out, which transmits the program as an FM RF signal which you tune your TV to; and audio and video out from RCA jacks. We have the signal coming into our TV via the audio and video out jacks. The decoder allows you to run your free-to-air antennae through the box for TVs that don't have audio/video inputs.

wheelinround
8th October 2007, 06:11 PM
Silent Trickie Dickie has WiFi antenna which allows just what you want to do no cables
http://www.dse.com.au/cgi-bin/dse.filereader?4709d90702eb90bc273fc0a87f9c06be+EN/catalogs/CTG0002674

silentC
8th October 2007, 06:15 PM
Yeah I thought about one of those. Thing is I've got enough coax cable to do it at zero cost but it would cost me over a hundred bucks to set up with the wireless gizmos.

r.byatt
8th October 2007, 07:00 PM
I use separate RF modulators to transmit Austar, DVD, and the VCR to all TV's connected within our house.

It's like being in a motel ch1=DVD ch2=Austar etc..

I just us a splitter in reverse to combine the output of the RF modulators and the incoming aerial signal and then us a splitter to direct the RF signal to the TVs.

The external RF modulators can be tuned to different frequencies (you can get them in UHF or VHF)which might move you away from the interference your seeing.

The ones I use also have controls on the volume and contrast to let you match up all inputs to the same volume etc.

I hope this helps

Robert

rrich
9th October 2007, 04:50 PM
Sorry Rich, the 2-way splitter I'm referring to is simply to allow you to feed the one signal to two different points - in this case I have a cable from my free-to-air antennae and I want to split it off to two wall sockets (only one will be used).

Ah, a splitter with one signal in and two signals out. I've seen two types here. One is good to about 800 Mhz while the other is good to about 2 Ghz. I don't know the low end but our lowest channel starts at about 54 Mhz. These splitters work on broadcast, cable and digital cable. A huge disadvantage when using a splitter with an over the air signal is that you will loose over half of the signal strength.

These splitters require coax at 75 Ohms. (If you are using old LAN coax at 50 Ohms it won't work. DAMHIKT)

From your initial description and if I had to guess, I suspect that the coax connectors may not be installed correctly. It just sounds like that kind of problem.

silentC
9th October 2007, 04:53 PM
I went to the electrical supplies place and bought some better connectors and other stuff today, so I'm going to pull it all apart and rewire from scratch. If it doesn't improve, bad luck - it's only for the kid's room!