tv point. extension?

Derek W

Derek W

Derek W

Soldato
Joined
1 Oct 2008
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I've got an odd question.

I moved into my house in September and I had to connect the existing analogue aerial in the attic to the tv point in the lounge. Hooked up my tv, panny st50, and everything works fine.

I now want to extend that point to the other side of the room. I've ran a cable behind the skirting to another tv point I cut in the wall and added a plug to the other so it can fit into the original tv socket.

When I plug the tv in it comes up with no signal. I've checked the connections and everything is fine. I've got a signal booster in but that doesn't make any difference.

The only thing I can see that's different is the cable itself as the new cable is termed as a digital coaxial cable with gold connections rather than the original analogue coaxial cable with silver connectors.

Would the change in cables and connectors make any difference?
 
Derek W said:
a digital coaxial cable
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No such thing (outside of the fantasy land of the Monster Company marketing shysters).
A coaxial cable is a coaxial cable and no amount of gold plating changes how it works.

You've made a wiring error somewhere, check the core isn't shorting to the shield or something :)
 
Yeah didn't think that would make any difference. I've already checked and sorted any stray wires which may have caused an issue.

Would it be possible that the signal might need boosted twice over the length and changes in cables?
 
Every joint in the cable increases attenuation.

How long is the extension and how far from the attic is the feed? Could be a length issue, although sounds like a wiring error somewhere along the way.
 
bitslice said:
No such thing (outside of the fantasy land of the Monster Company marketing shysters).
A coaxial cable is a coaxial cable and no amount of gold plating changes how it works.

You've made a wiring error somewhere, check the core isn't shorting to the shield or something :)
Click to expand...

Well... that's not strictly true, you can get CoAx with different impedances which are designed for different applications, some for transmitting analogue data and some for transmitting digital data. Granted, different types of CoAx usually have different terminators/connectors, but the point stands that a TV CoAx Cable, if forced to connect to say, a Virgin Media Cable system, will fail to function correctly :)
 
EVH said:
Every joint in the cable increases attenuation.

How long is the extension and how far from the attic is the feed? Could be a length issue, although sounds like a wiring error somewhere along the way.
Click to expand...

There's a ten metre length from aerial in the attic to the wall socket in the lounge. I've extended it 4 metres from that wall socket to the other. I use a single booster from the wall socket to the tv. I did try with a booster after each wall socket by didn't work. I'll check my connections again tomorrow since I'm away all day at the football.
 
Boost as close to the arial as possible (in the loft). Dont bother boosting again. Id suggest your new cable has a break in the core or you are letting it touch one of the shielding wires. Also make sure tge shield toouches outside of any plug/socket
 
Aod said:
Well... that's not strictly true, you can get CoAx with different impedances which are designed for different applications, some for transmitting analogue data and some for transmitting digital data. Granted, different types of CoAx usually have different terminators/connectors, but the point stands that a TV CoAx Cable, if forced to connect to say, a Virgin Media Cable system, will fail to function correctly :)
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What a load of rubbish. Virgin use 75 ohm coax, exactly the same as will be used to a standard TV aerial on the roof or to a Sky dish. The quality may be different but all TV is 75 ohms.

It sounds like there's either a short or a break in the extension somewhere, adding 10m of cable wouldn't cause a complete drop out of signal.
 
Feek said:
What a load of rubbish. Virgin use 75 ohm coax, exactly the same as will be used to a standard TV aerial on the roof or to a Sky dish. The quality may be different but all TV is 75 ohms.

It sounds like there's either a short or a break in the extension somewhere, adding 10m of cable wouldn't cause a complete drop out of signal.
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ive seen coax rated at 60 and 50 ohms, not that it realy makes a differance,
 
Then the person who installed it is an idiot. All TV stuff should be 75 ohms.
 
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Aod said:
Well... that's not strictly true, you can get CoAx with different impedances which are designed for different applications, some for transmitting analogue data and some for transmitting digital data. Granted, different types of CoAx usually have different terminators/connectors, but the point stands that a TV CoAx Cable, if forced to connect to say, a Virgin Media Cable system, will fail to function correctly :)
Click to expand...

Providing the shielding is up to scratch I doubt it would fail. You want 75ohm for low impedance, so anything using a dish or aerial will use that, as does a cable modem connection.
Other ratings are generally used in active transception, very high frequencies and so on.
 
Feek said:
What a load of rubbish. Virgin use 75 ohm coax, exactly the same as will be used to a standard TV aerial on the roof or to a Sky dish. The quality may be different but all TV is 75 ohms.

It sounds like there's either a short or a break in the extension somewhere, adding 10m of cable wouldn't cause a complete drop out of signal.
Click to expand...

soundood said:
ive seen coax rated at 60 and 50 ohms, not that it realy makes a differance,
Click to expand...

malfunkshun said:
Providing the shielding is up to scratch I doubt it would fail. You want 75ohm for low impedance, so anything using a dish or aerial will use that, as does a cable modem connection.
Other ratings are generally used in active transception, very high frequencies and so on.
Click to expand...

Hehehe, I suppose that I was thinking of old Coax Ethernet Networks which would be seriously unhappy if you decided to try and use a bit of TV cable for a link Segment :p
 
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