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Opy

TV Aerial Socket

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This horrible thing is installed here.

It's an old 300 Ohm TV aerial socket.

With old 300 Ohm ribbon cable going up the wall cavity.

Judging by the wiring at the back of it there is a good chance that it was a DIY installation. I doubt it's a fire hazard as there's not a lot of power going through here.

 

I want to use it for a digital TV.

So I want a 75 Ohm coaxial socket.

 

Questions for the Atomic electricians :

One day, I'll see channel 10 again.

One day.

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please try and report back. I wanna know too.

 

all websites online read as if the 'patch lead' is the only OHM important part. the rest is effectively straight through minimum resistance... but who knows... (someone will, but not me)

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Digital or analogue makes no difference as far as your antenna cabling goes. What does make a difference is the old ladder stuff is completely shit and needs ripping out and replacing with some decent shielded coax.

Questions for the Atomic electricians :

1) Yes replace the whole lot. Ribbon is useless. Use quad shielded RG6 like http://dicksmith.com.au/product/W2087/high...ielded-tv-cable

Also grab a http://dicksmith.com.au/product/T3640/rotary-coax-stripper makes stripping the cable a lot easier.

Wall plate http://dicksmith.com.au/product/P2110/pal-...ll-plate-outlet unless you want to go the complication of going F type crimp terminals.

Use the existing ribbon cable to pull the Coax through, should be reasonable easy to do.

 

2) Waste of time do it properly

 

3) Nope, one of the few things you don't need a licence to do these days.

 

As far as channel 10 going missing check your actual antenna as it may not be suitable for the new frequencies that are used by some of the digital channels.

http://www.dtvforum.info/index.php?showforum=21

has some info for NSW viewers.

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Thanks aliali

 

I'm using an indoor antenna at the moment. We have to turn it 90 degrees depending on if we are watching channel 7 channels or channel 9 channels. All of the 10 channels are just not available (or the antenna was pointing in a bad way during the last scan).

 

I'm getting an electrician in to install lights, power sockets, ceiling fans and ethernet sockets, so I'll just get him to get into the roof to replace the ladder ribbon. I might supply the cable and wall plate though.

 

I don't know what's on the roof yet. Can't see an aerial from the driveway and back yard is too small to get an angle, even on a ladder. I wonder if they'd install one inside the roof. I've heard of crazier things.

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Check out bunnings price on the quad shielded cable, last time I brought some there it was less than a dollar per meter.

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Opy, is your current antenna amplified? they can do wonders on digital (despite being useless on analogue caus you amplified noise as well :P)

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Opy, is your current antenna amplified? they can do wonders on digital (despite being useless on analogue caus you amplified noise as well :P)

they worked just as well on analogue as they do on digital and they still amplify the noise so they work best in areas of freinge reception and low noise

you will notice some receivers have signal strength and quality

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Used an amplifier on a pre-digital (though still coax) setup years ago. It was a great help and still is being used today.

 

I just stuck my head up into the roof.

 

It's hard to see, but it looks like a coil of cable and maybe some sort of plug on the end.

Posted Image

 

So there is no aerial and no amplifier.

 

I remember throwing a line of coax from my mate's TV across the room and that was all that was needed to allow us to watch South Park. Maybe that's what they were trying to do here, just use the cable itself as an antenna. Dodgy.

 

Strata will need me to use a professional installer, so I'll let them worry about it from here on in.

 

Thanks for the help Atomicans.

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Opy, is your current antenna amplified? they can do wonders on digital (despite being useless on analogue caus you amplified noise as well :P)

they worked just as well on analogue as they do on digital and they still amplify the noise so they work best in areas of freinge reception and low noise

you will notice some receivers have signal strength and quality

 

Sorry I wasnt too clear;

I meant human perceivable noise. On analogue, while you'd often say, improve color or audio, you might increase 'snow' too. Usually something 'gave way' when an amplified antenna was ued on analogue in my experience.

Ive had way better luck with digital due to error correction etc.

 

Which is also worth a note; some brands of set top box handle bad reception where others dont. None will admit this though, look on google for brands.

 

Oh, also, http://blog.makezine.com/2009/01/23/maker-...tenna-steadyca/

They work AMAZINGLY well, I've not made one myself yet but a mate did and got the full range. Sick of cheap bunny ears thats for sure.....

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Just watched 2 episodes of Futurama. Didn't even know it was still on the air. Having access to Channel 10 again is pretty okay so far.

 

Cost me $396 for complete install of antenna and they made a port to TV coax cable for me on the spot.

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Just watched 2 episodes of Futurama. Didn't even know it was still on the air. Having access to Channel 10 again is pretty okay so far.

 

Cost me $396 for complete install of antenna and they made a port to TV coax cable for me on the spot.

Nice :-). Been ages since I've seen that

 

EDIT: Reminds me, I need to buy a cable myself, as the bunny ears antenna I found in this apartment is absolutely useless, and I found a wall socket that is hopefully still wired up

Edited by nobody813

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Just watched 2 episodes of Futurama. Didn't even know it was still on the air. Having access to Channel 10 again is pretty okay so far.

 

Cost me $396 for complete install of antenna and they made a port to TV coax cable for me on the spot.

That seems very expensive for what they did. A HDTV antenna kit usually costs around $175 to $200 . As for Labor costs i think they took advantage of the fact that it was for HD TV upgrades. Did they leave a printed invoice ? Kinda think they might also be reclaiming part of the install as part of Digital TV Ready program.

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Which is also worth a note; some brands of set top box handle bad reception where others dont. None will admit this though, look on google for brands.

Mmm true. I recently a $40 STB from dick smith for a HD CRT telly I had lying around for the kids. Problem is it doesn't get any ABC channels (so no channels 22 and 23). My other two TV's get it no problem. 1 being the inbuilt tuner on my tv as well as the dual tuner for my HTPC on the same TV, as well as the USB tuner on my PC. Possible the connection is shit in the kids play room. I'm yet to test the Dick Smith STB at any other point.

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all websites online read as if the 'patch lead' is the only OHM important part. the rest is effectively straight through minimum resistance... but who knows... (someone will, but not me)

All transmission lines and connectors of an RF circuit need to be impedance matched. In the home, this will be determined by the receiver (so, STB or TV).

 

With mismatched parts, you end up with signal reflection, ringing, attenuation, and other effects that can produce red-herring symptoms.

 

That's why the coathanger design you linked has a balun on it, to match the 300ohm antenna design to your 75ohm equipment.

 

http://en.wikipedia.org/wiki/Nominal_impedance

Edited by SquallStrife

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