Coax over Ethernet?

[nero44]

Hello Everybody,

as the title suggests... I know there are tons of videos/tutorials, explaining how you can re-use existing coax cables in your house as ethernet connection, but I am looking to do the reverse...

Background:
I want to split my antenna signal and have one end go to my TV and the other end to the kitchen into a "multimedia" wall unit that can also play radio. A year ago I laid two ethernet cables under my floor to a a reachable location, one of them in theory could be a spare. Is there a way to use this existing ethernet run for a coax/antenna signal? Or do I need go ahead and lay a dedicated coax cable for this?

 

[spile]

Not possible - use new coax but given the move to IP, I would look in that direction.

 

[pete01]

Worth a try for 7 quid?

 

[endecotp]

Worth a try for 7 quid?

They might kinda work for something like CCTV, but I’d be amazed if they worked for a TV aerial signal.

(If you do try, please let us know what happens!)

 

[spile]

You will need a balun. AI did a better job than me to show why this won’t work…

“Using a network cable for RF signals fails primarily because of a fundamental mismatch in physical architecture and electrical properties. Coaxial cables are "unbalanced," using a single shielded conductor to trap high-frequency waves, whereas Ethernet cables are "balanced," using twisted pairs that lack the necessary shielding to prevent high-frequency RF from leaking out or picking up interference. This results in extreme signal attenuation (loss of strength) and an impedance mismatch (75 Ohms vs. 100 Ohms) that causes the signal to reflect and distort. Without an active "Balun" or powered extender to transform and amplify the signal, a simple passive adapter cannot bridge the gap between these two different transmission methods.”

 

[Rodders53]

HD Homerun or similar box (Media Server/NAS/PC with UHF DVB-T2 tuners) on the end of the coax from the aerial and then serve the desired TV/radio channels to smart TVs, media players over ethernet and/or wifi.
e.g. https://www.silicondust.com/hdhomerun/


Note that splitting an aerial feed to two TVs will, passively split, lose over half the signal available (-4dB per way). It may or may not matter depending on the signal level at the dwelling and the aerial concerned.
Use decent quality all copper (core, braid and foil tape) foam-filled cable such as Webro WF100.

 

[endecotp]

AI did a better job than me to show why this won’t work

Still not very accurate though.

 

[nero44]

All good ideas thanks. Will checkout these baluns, but it seems they need to be powered with some DC power, so additional socket. Not sure maybe it will be easier to just get under the floor and lay a fresh coax.

 

[endecotp]

maybe it will be easier to just get under the floor and lay a fresh coax.

Yes.

 

[Harry Bloomfield]

A year ago I laid two ethernet cables under my floor to a a reachable location, one of them in theory could be a spare. Is there a way to use this existing ethernet run for a coax/antenna signal?

Not sensible. Easier, would be to run Internet to the TV, and use IP TV, catchup etc.

 

[nero44]

Not sensible. Easier, would be to run Internet to the TV, and use IP TV, catchup etc.

It's not for TV. My TV is already connected to internet and aerial and that's all working fine.

I am redoing my kitchen later in the year and want install a wall mounted audio system (e.g. q-accoustics e120). For that I want to lay the groundwork and get the antenna signal to the desired location. It's just one additional run of say 10m, so I expect the tv signal to be unaffected, but if it becomes bad I can always put an amplifier in-between. Signal strength is generally v. good here at my location.

 

[flameport]

a wall mounted audio system (e.g. q-accoustics e120).

That has an FM/DAB receiver, not a TV.
FM and DAB frequencies are unrelated to those used by TV, shoving a TV aerial into it isn't likely to work well or at all.

It's primary function is to receive audio wirelessly from another device, and as the vast majority of radio stations are available on streaming in far better quality than DAB will ever provide, why do you need an aerial input?

 

[Lucid]

It's not for TV. My TV is already connected to internet and aerial and that's all working fine.

I am redoing my kitchen later in the year and want install a wall mounted audio system (e.g. q-accoustics e120). For that I want to lay the groundwork and get the antenna signal to the desired location. It's just one additional run of say 10m, so I expect the tv signal to be unaffected, but if it becomes bad I can always put an amplifier in-between. Signal strength is generally v. good here at my location.

I think flameport has a point here. If you're not planning on having a TV in the kitchen, then running the TV aerial signal to the room is sort of pointless.

Retailer aerialsandtv did some tests to check FM and DAB reception with various types of aerials. You can see the chart of their results here. The bottom line is that TV aerials were rated poor to useless for both FM and DAB reception. That's not too surprising though. They're tuned to significantly different frequencies. FM runs in the 87.5–108.0 MHz range. DAB is 174–240 MHz. These are both VHF frequency ranges. Digital TV is in the next band up - UHF. It's 470MHz to 700MHz

If this were visible light, the range separation would be something like this. It's not precise, but you should get the idea each is in a different portion of the range, so looking for red and for orange light in the green to violet portion of the spectrum shouldn't give anything at all.

ATV noted that there were very weak radio signals from TV aerials. They put this down to the longer booms on the YAGIs acting a bit like a poor FM/DAB antenna.

You might have something else in mind, but if it is only for FM and DAB, then I'd hate to see anyone wasting their time with baluns or with running coax when there's very little chance they'll get any useable signal if there's just a TV aerial installed.

DAB and DAB+ is kind of okay for the car where you've got a lot of background noise to mask the loss of quality. It's not so good for home listening though. I see that the Q Acoustics wall amp has additional inputs. Maybe have a look at something that can bring internet radio to the table, again, as suggested by flameport.

A Wiim Amp Pro tucked away integrates music streaming, Internet radio, direct inputs (including ARC should you decide to have a TV there in the future), Bluetooth for your phone connections, and there's a subwoofer out which is kind of a handy way to beef up the sound. Control is via smart phone app, and that can be run on a tablet too if you want some local control always present. The Wiim product is a bit more money than the Q Acoustics, but I think it is more futureproofed and so worth it. There's a decent review of the product here.

 

[Harry Bloomfield]

It's not for TV. My TV is already connected to internet and aerial and that's all working fine.

Internet radio then..