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Propagating a Signal Through Old Walls?
avjewe asks: "I have a wireless (802.11) network in my 100 year old house. The walls are thick plaster, with enough metal in them to block the signal quite effectively. The floors, however, pass the signal just fine. Does anyone have any experience or suggestions as to how one can propagate a signal through a maze of faraday cages? I recently added an omni-directional antenna which, as one would expect, boosted the signal where I already had one, but didn't help the dead spots."
I realize it has some downsides from the aesthetic point of view, but, really, what's more important?
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You might be able to connect multiple transmit and multiple receive antennas to the same access point. I don't know how well it'd work, especially with the receive portion.
Have you tried putting the WAP in the attic? Perhaps there isn't metal in the ceilings?
Great ideas often receive violent opposition from mediocre minds. - Albert Einstein
Anybody have experience with Powerline technology in the home?
d =3 4&scid=33&prid=416
http://www.linksys.com/products/product.asp?gri
I've heard Siemens also has some good gear. Better than Linksys?
I dont know if its possible, but could you actualy use the metal in the walls as an antenna? Just expose a part and attach your AP directly to the metal in the wall?
-- Senior Software Engineer, Attorney appearance services, locallawyerapp.com.
You could take two antennas, and connect them with LMR. Put one antenna in an area with signal, and the other in a dead zone. Each antenna will catch some of the signal for the other to radiate. Granted the losses are high, but you can bend radio around a wall.
Do what parent does, if you really need wireless in each room then add an access point at each drop where you have you cabling. Its not that bad really, access points are getting very cheap and you can start with as many or as little as you want.
My house is old, real old. We have wires running inside old gas light tubes for conduit and lots of knob and tube to mess with signals. The radiators don't seem to be much trouble, unless you're tx/rx ing right in front of one, course they are by the windows so it's never a problem. And yes, we have the old old plaster - very think stuff. Can't even nail in it. Still I managed to find a central location for my little netgear mr814v2 with a stock antenna to do its thing, after some trying. My perfect spot was at the VERY top (9ft up from 1st floor level - we have high ceilings) of the basement steps - attached to the ceiling. From this location it was: a) in the center of the house (very little signal leakage to outside world) b) in between the first and second floors c) hidden away where I could forget it was there and just use it. My advice is - mount it up a wall in the center of your home. Higher the better. For me... this was enough. I still have dead spots where the oversized central 19th century chimney simply refuses to pass a signal. That just means you have to sit on the OTHER sofa to check your email.
I know it doesn't have the coolness factor of WiFi, and it doesn't help you contribute to the criminal deliquency of your neighbors' little wannabe hacker kids, but you could try regular old CAT5, just tack it down along the edges of the walls somewhere and cover it up with some moulding.
11*43+456^2
solder one pole of your antenna cable to one end of
the wire mesh behind the plaster, and solder the
other pole to the other end of the mesh. Voila,
what was previously shielding has become your
antenna.
-I like my women like I like my tea: green-
Write in from my little sister: Drill little holes and put picture frames over them
-------
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Your problem is that you want to get network access to all parts of your home with a minimum of fuss, ideally wireless.
The walls prevent a single wireless access point from working throughout your home.
Your implicit question is: How can I, without investing in more equipment, get wireless throughout the home?
The answer is: You cannot.
Solutions:
1) Place multiple access points throughout the home. Honestly, you can get one for $19 now - why are you so worried about it?
2) Wire passive repeaters throughout the home. Get two 802.11 antennas, put one on each side of the various offending walls, and connect them with their very short cables through the wall. Not great, causes other small problems, but recent radios and APs can sort those out with some loss in quality and speed.
3) Use APs with two antennas, and mount an antenna on each side of one wall. Means you don't have to have an AP for each section, one AP can serve two sections.
4) Use wireless bridges and repeaters - again, one antenna on each side of a wall.
5) Use an amplifier with your AP. DLink, Linksys, etc - they all have amps. Mount the AP and both antennas in the attic. Spread the antennas out, 20-30 feet apart to get the largest cover area.
6) Use a powerline to wireless adaptor, and place them all over the place. Should be able to buy these very cheaply online now.
There are many other solutions, but these are the ones that come to mind readily and should be easily implementable by even the most technophobic individual.
Hopefully you know how to repair cracks and holes in plaster.
-Adam
If you place your AP in the right location, maybe the reflections will make there way through the house to construct at the dead spots.
You could stick passive "repeaters" in the walls. This would consist of an antenna attached to an antenna, so the signal gathered by one would be radiated from the other. This would involve holes though...if you're running holes, might as run LAN cables through them.
While I've never messed with wireless it occurs to me that you may be able to put the access point on the roof or the side of the building and put the antennas outside.
"Flyin' in just a sweet place,
Never been known to fail..."
don't worry, you're living on borrowed time. that plaster's about reached the end of its lifespan, and when you have to put up sheetrock, problem solved!
but seriously...
i have a similar situation, and i solved it by using my cellar to poke up cat5 and repeaters. (i've got a 65 year old house, but it's plaster *on* sheetrock- best of both worlds) my faraday cage used to drive me nuts- move 6 inches over, lose a signal. i just hid the repeaters behind furniture. *note* - i am a bachelor.
somebody needs to make a repeater/access point that fits in an electrical outlet wall-box, btw. what with schools wanting wireless everywhere, that would make it easy to do. i digress, however.
now, if you need to run cable, the trick some people do in old houses- take off the- aw dang it, words fail me. the boards around the periphery of the room, on the wall? take those off, and then raise em up about half an inch- run the cable there, and put quarter round molding in front to hide the gap and wire.
similarly, you can hide wire behind a picture rail. drilling a hole through plaster is always fin, though, as you know. (i always start a hole with, like, a 1/16th inch bit, then after i've drilled through, go back with the size i really need.)
if you try any of the verious antenna repeaters, let me know. i'd like to get a signal outside in the backyard...
stored on computers from birth to the grave
I guess that's a workable solution -- as long as you don't obsess over silly little issues like "Does that beam help hold up the roof?"
Current wiring standards use either 4 or 8 wires in a twisted pair setup. Power lines provide only three wires and there is no guarantee you will find a nicely twisted pair there.
Tim
Omnia vestra castrorum habetur nobis.
http://webphysics.davidson.edu/Applets/Poisson/Far aday.html
my house was built in 1875 (in the UK, in a little conservation area called "Dodge Hill". That's where the Dodge family of Dodge City and Dodge Motors came from...) and it's great: a victorian house that's full of character, built back when you had craftsmen doing everything by hand. it's chock full of high tech, too. whilst a lot of modern houses may be looking a little rough in 100 years, a lot of older ones don't.
Most fairly modern houses (built in the last hundred years) have pretty standard construction. Lath and plaster is a bitch to patch up, so make your cable holes small, and if possible in corners where you can hide them with stuff.
If that's too much typing for you,(without any spaces put there by Slashdot) yields: http://webphysics.davidson.edu/Applets/Poisson/Fa
My house built in 1954, is plaster. I have a 802.11 AP and can get signal 3 houses down on each side of me and to the street behind.
Where does this metal come from and what is it for?
Your linksys has 2 antennas. Perhaps you can run one with coax to a new location and end up with a better line-of sight. Like move an antenna to another room, so they have different visibility?
It's a hack, and I don't know if the router can handle it, but it could work.
Slashdot's rate-of-post filter: Preventing you from posting too many great ideas at once.
Well... I live in a 12th century castle (Ok, ok...not technically a castle, but most Americans would call it a castle) with walls that are four to six feet thick. I tried wireless exactly once for about an hour. Gave up quickly and I just have duct taped Cat5 to the raw stone ceiling now.
Life is tough in medieval europe.
then she agreed to the cables run behind the molding...
3 strands of cat 5, and 5 rca lines... wheee!
every day http://en.wikipedia.org/wiki/Special:Random
I have the same problem in my house. For us (we're renting and can't make mods to the house) the simplest answer was to use ethernet to powerline bridges. Plug the brick into the wall, plug your ethernet into it, and all the computers on the network are sharing the powerlines at 14 Mb/s.
It's not terribly fast, but it's easy and reliable. All the adapters I've seen come with DES encryption built in, and you'll wanna set that.
Have you looked into radiating cable (aka leaky coax)? It's useful stuff. In effect, it's an antenna distributed along the length of the cable. I've used it to get cellular coverage into a metal-walled room. A little more elegant than APs everywhere...
I have a girlfriend whose name doesn't end in
Just a nit, CAT-5e isn't Gigabit copper. CAT-6 is. CAT-5e can only handle 250 MBps on Ethernet.
Matthew G P Coe
http://mgpcoe.blogspot.com/
So far, I've had no trouble at all using the units across circuit breakers. They're designed to work that way, even.
If you happen to have a circuit breaker that has surge protection at the panel (VERY rare), it won't work. Also, don't plug the unit into a plug strip or surge protector. Surge protectors filter out the frequency range used by the power line equipment, so you really do need to plug it directly into the wall. However, if you're concerned about surges coming over the wiring, don't worry. The units have their own protection.
Remember, the MAX for this stuff is 14Mbps, but you'll probably get 6 or 7 at best, which is still very good. Good luck!