Greetings, folks...
Not EXACTLY ham-related, but since there's about a metric buttload of
smarts on radio topics here, figured I might get some useful input.

The situation:
Guess-timated 800 feet of co-ax "abandoned in place" between house and
outbuilding. Once supplied CATV signal to apartment in the outbuilding,
now connected to nothing at either end. I can't find any definitive
markings on the exposed sections to tell me precisely what "flavor" it
is, but I'd suspect it's "just plain old Cable TV wire" - RG-58?

The goal:
Run a computer with an 802.11 card (2.417-2.467 GHz) in the
outbuilding's apartment, and have the wireless connect to the router in
the house. Not possible at the moment due to lack of signal. ("No access
point in range" diagnostic from the card's 'ware.)

Secondary goal:
Spend little or no $$$ in the doing.

The restrictions:
The owner of the router in the house forbids ANY modification of the
router - no screwing one of those fancy 802.11 range extender antennas
onto the beast, etc., but if I can do it using other methods, I'm
welcome to.

The thought:
Attach a properly tuned antenna to each end of the co-ax, position the
one at the house end as near the router as possible, and park the
machine in the apartment near the other end. I'm thinking a sort of
"radio pipeline" here.

The workability:
That's where you guys come in! Does this plan fall into the "utterly
hopeless - you're nuts!" category, or is it a "Might work, if you
sacrifice a goat over the contraption during the dark of the moon whilst
chanting to the wireless gods" concept? Or better yet, is it a case of
"It should work just fine!"?

Any thoughts/suggestions welcome...

Thanks in advance!

--
Don Bruder - - If your "From:" address isn't on my whitelist,
or the subject of the message doesn't contain the exact text "PopperAndShadow"
somewhere, any message sent to this address will go in the garbage without my
ever knowing it arrived. Sorry... http://www.sonic.net/~dakidd for more info

Since you have so much signal at the router, you might get away with it, even
though there will be a lot of loss in the coax. Incidentally it is probably
RG-59.
Technically, it will work (the antennas and coax will transfer the signals
between the two locations).
I'd say you have a good chance at success.

Rick K2XT

No way you are going to get any significant amount of the Router's 40 or
50 mW of 2.4GHz signal out the other end of 800 feet of that cable, be it
RG59 or RG6.

Three options come to my mind at the moment. 1) try a high gain
(directional) WiFi antenna at the outbuilding end only to try and get a
signal. MFJ makes a tiny yagi for that purpose. 2) possibly obtain
another WiFi Router or bridge of your own and connect it by ethernet cable
to a port on the owner's router, thus having your own wifi router to play
with by adding directional antennas, etc. 3) install a wifi bridge unit
somewhere in between the two locations...

I believe there are possibly other ways, too, but I haven't had my
morning coffee yet, so that's all I can come up with at the moment.

Ed

In article ,
Rick wrote:

Since you have so much signal at the router, you might get away with it, even
though there will be a lot of loss in the coax. Incidentally it is probably
RG-59.

One on-line coax-loss calculator indicates about 144 dB of loss in
RG-59, at 2.4 GHz over an 800-foot span.

Added to the antenna losses at both ends, and I have real doubts as to
whether a usable signal will result. It *might* work if the 802.11
radios were plugged directly into the coax, with no antennas involved,
but that does not sound feasible.

I'd say you have a good chance at success.

I have serious doubts.

I'd suggest another approach - use the coax to carry wired Ethernet
(perhaps with a simple 1.5:1 unun at each end). Losses will be far
lower at 10 MHz than they are at 2400 MHz. 10Base2 (over RG-58) is
spec'ed for up to 600 feet per segment, and 10Base5 (over RG-8) will
go more than 1500 feet.

It'd be necessary to install a 10BaseT-to-10Base2 bridge next to the
router, and some other sort of 10Base2 termination at the outbuilding
(another bridge / router / access-point).

Although most consumer-grade Ethernet products on the market these
days are 10BaseT- or 100BaseT-only, it's possible to find older
Ethernet hubs and switches with 10Base2 BNC jacks fairly easily on the
surplus market.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

One on-line coax-loss calculator indicates about 144 dB of loss in
RG-59, at 2.4 GHz over an 800-foot span.

Added to the antenna losses at both ends, and I have real doubts as to
whether a usable signal will result. It *might* work if the 802.11
radios were plugged directly into the coax, with no antennas involved,
but that does not sound feasible.


If you get a pair of preamp/power amp modules, like these:
http://cgi.ebay.com/2-4GHz-802-11b-1-Watt-WiFi-amplifier-signal-booster_W0QQitemZ5845608031QQcmdZViewItem?hash=ite m5845608031&_trksid=p3286.c50.m20.l1116
and use them at both ends of that long run of coax, it might work. But
at $186 times 2, that's rather expensive for something that's not
guaranteed. At least, with the amps feeding directly into the coax, you
probably would have a minimum of interference from other wifi users and
microwave ovens.

In article k.net,
robert casey wrote:
One on-line coax-loss calculator indicates about 144 dB of loss in
RG-59, at 2.4 GHz over an 800-foot span.

Added to the antenna losses at both ends, and I have real doubts as to
whether a usable signal will result. It *might* work if the 802.11
radios were plugged directly into the coax, with no antennas involved,
but that does not sound feasible.


If you get a pair of preamp/power amp modules, like these:
http://cgi.ebay.com/2-4GHz-802-11b-1-Watt-WiFi-amplifier-signal-booster_W0QQitemZ5845608031QQcmdZViewItem?hash=ite m5845608031&_trksid=p3286.c50.m20.l1116
and use them at both ends of that long run of coax, it might work.

Even that might be marginal.

One site I Googled stated a WiFi receiver sensitivity of -76 dBm. A
typical WiFi card has a transmitter output of around 15 dBm, and
access points may be up in the 20 dBm range. That'll allow for only
about 100 dB of attenuation between transmitter and receiver before
you can't get a good connection any more... and the estimate for the
RG-59 coax was 45 dB worse than that.

Boosting the power to 1 watt will give you between 10 and 15 dB of
additional signal... still far short of the 45 dB of additional power
and/or sensitivity needed for a connection.

Running 2.4 GHz over thin cable is just sorta silly... especially when
there's a decades-old, well-tested, and very reliable cable-based
technology which will give equal or better data rates due to much
lower attenuation at lower frequencies.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

"Dave Platt" wrote in message
...
In article ,
Rick wrote:

Since you have so much signal at the router, you might get away with it,
even
though there will be a lot of loss in the coax. Incidentally it is
probably
RG-59.

One on-line coax-loss calculator indicates about 144 dB of loss in
RG-59, at 2.4 GHz over an 800-foot span.

Added to the antenna losses at both ends, and I have real doubts as to
whether a usable signal will result. It *might* work if the 802.11
radios were plugged directly into the coax, with no antennas involved,
but that does not sound feasible.

If you loss on the cable is correct it will not work even if the computer is
wired directly to the router. If I remember correctly a router puts out
about a plus 20 db signal and the rx requires about -86db. Ive done this
between two building where a big low loss 75 ohm hardline was already in
place. just barely getting enough signal at 500 yds.

Jimmie