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In an older house, the wire mesh in walls surrounding the furnace behave like a Faraday cage and block wifi signals. It is also difficult to lay new cable, however there is television cable to multiple locations due to there once having been a roof-installed, television antenna.

It would be relatively trivial to install the wifi router at the center distribution point, then have the antenna broadcasting/receiving the signal plugged in at each of the old television outlets.

I assume that it would not be too difficult to find an adapter for SMA <-> F-type connectors. The cable is actually RG-59 rather than RG-6, but I assume that it still has relatively good RF isolation along its length, which is no more than a couple hundred feet in any direction.

Does anyone know a problem with the idea? Will a router get confused if there is /too little/ interference between the two antenna? Is that length of cable (~100ft) too long for the signal a router broadcasts?

I have seen that it is also possible to use old ~$30/each FiOS cable modems available on eBay to extend a network over television cable. However, that seems like a less elegant solution, and might interfere with upnp and dlna services I'd like to have work on a single network.

Thanks if anyone has answers or suggestions before I try this project!

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Why can't you just use the Wireless router as it was intended, like without wires? –  Chris S Jan 16 '11 at 21:55
    
@ Chris S, did you read the first paragraph? –  Moab Jan 16 '11 at 22:37
    
@Moab, unless your putting the router or computers inside the furnace, a Faraday cage only blocks signals inside the cage, it doesn't suck them out of the house like a vacuum cleaner. –  Chris S Jan 16 '11 at 22:51
    
If it is in between the router and the PC by line of sight it can block the signal, signals radiate out from the antenna and do not turn corners. That is by definition what a faraday cage does, routes the signal that hits it to ground, not sucking, but Blocking it from reaching its destination. –  Moab Jan 16 '11 at 23:01
    
Ok, we're not perhaps talking about the router being in a Faraday cage, but the wire mesh will certainly attenuate the signals if it's in the direct path between transmitter and receiver. –  Linker3000 Jan 17 '11 at 13:34
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migrated from serverfault.com Jan 16 '11 at 21:54

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4 Answers

Hmm. I think this could be problematical.

Depending on which type of tv reception antennas were used some of infrastructure components (divider,amps,outlets) may cut of or interfere the signal. For example: Old terrestrical VHF/UHF tv reception used frequencies from 47Mhz to 862 MHz, satellite signals downmixed by a lnb use 950 to 2150 MHz. Wifi uses frequencies ranging from 2400–2483 MHz and 5150 to 5725 Mhz. Some old tv outlets terminate the signal with a 50/75 Ohm resistor.

And: Wifi antennas are desinged for a special wavelength; if you combine them serial or parallel, the signal transmission reception would be a mess. And you would "contaminate" your are with a lot of interferences in all possible frequency ranges.

I would not do it. If you try it, keep us informed! :D

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I like generic, easy to replace, easy to install, easy to maintain and hate special connectors that take things out of spec.

The idea here is extend the wireless network around the black whole. This is already SPECIAL. So, here is my special suggestion to work around the black hole.

I would assume a secondary repeater (dd-wrt, tomato etc) would work around corners just fine with the correct angles assigned around "The box". This would require one routers AND one repeater.

If you have these two and want them both wired you could use the something LIKE this below link "Wall-Plugged Ethernet Extender Kit" that uses your house AC plugs/wires with STANDARD RJ45 ethernet wire/connectors and it would also work(easily?)

http://www.bhphotovideo.com/c/product/464594-REG/Netgear_XE102GNA_Wall_Plugged_Ethernet_Extender_Kit.html

Asside from your network settings. I could see any "new out of the box" routers working perfectly for you with nothing special except 2 routers, 2 -more- RJ-45 cables and 2 AC network extenders.

Wireless Router1 LAN to AC-1 -> AC-2 to Wireless Router2 WAN. Plug and Play no?

Want to get fancy? Add a WDS network so there is only one wireless network name in the house.

This Wall=plugged Ethernet network extenders are made with different spec's by different manufacturers but all of them are FCC compliant or are supposed to be. So, forgive me please when I say that they are all the same and I am wrong.

Hope I helped and didn't waste your time. (wavE)

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Use a MoCA Net:

Pickup some Verizon Actiontec boxes normally used for FiOS or MoCA to Ethernet boxes and hook these up in place of your entire Wi-fi setup. It broadcasts at 1 GHZ and can make it through splitters. It was designed to wire up a house with Ethernet. Don't buy new! Using these you can get 208 Mb on the MoCA.

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Stefan has pretty much covered all the angles. Looking at the spec of RG-59 coax, it has fairly high attenuation at 1GHz+ and so using it at wifi frequencies will be very hit and miss. RG-59's nominal impedance is also 75 Ohms and the 802.11 standards are based on 50 Ohm loads so there will be a power transfer mismatch between the coax, antennas and transmitter/receiver units, further attenuating the signals.

I'd recommend siting the wifi router to cover one side of the building as best it can and use a pair of mains network adaptors ('powerplugs') to carry a network link to an access point that covers the other half - adding more powerplugs and APs if necessary.

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