"Highland Ham" wrote in message
...

Having followed today's postings on this topic , I see that there is a
wooded area between your house and shed, hence there seems to be no free
line of sight between the house and the shed.
That's why it is difficult to calculate/predict the Gain you need to
penetrate the wooded area with a 2.4 GHz signal.

YES - exactly.

I have been able to go laptop to laptop almost a mile with normal PCMCIA
cards, using patch antennas. (Well - normal cards modified to bring out the
signal to the antenna.) These antennas can be astonishingly directional.
Indeed, at 2.4 MHz, it is pretty easy to get antennas with amazing amounts
of gain. This translates into VERY CAREFUL aiming of the antenna. Also keep
in mind that at 2.4 GHz, RG-58 ain't gonna cut it. Most of what you put in
to one end of any normal coax will be sucked up by the coax and won't make
it out the other end. You need to use cable appropriate to the frequency.

With a wooded area, not only is it very difficult to calculate, but tiny
differences in the positioning of the two ends is going to make a huge
difference, as is summer to winter. Even a windy day is going to change
things.

Because of the small size, it can be pretty simple to build a yagi for
wireless. Yagis won' t have the gain of some of the other types of antennas,
but at the same time, they won't be nearly as critical.

Depending on your situation, you may find a directional antenna a better
choice than more power. Lots of people driving by like to "borrow" your
wireless, and I personally don't like the idea of strangers roaming my LAN,
even if they aren't typical crackers. (Seems to me that salesmen are the
most common intruders. They have learned that they can find a wireless
connection almost anywhere). I find getting coverage into the back yard,
while NOT getting coverage well into the street is a bit of a challenge.
Yes, I use encryption and MAC filtering, but I'd still rather not have lots
of wardrivers trying to break in.

...

xpyttl wrote:

I have been able to go laptop to laptop almost a mile with normal PCMCIA
cards, using patch antennas. (Well - normal cards modified to bring out the
signal to the antenna.) These antennas can be astonishingly directional.
Indeed, at 2.4 MHz, it is pretty easy to get antennas with amazing amounts
of gain.

There are restrictions on the RADIATED power, transmitter output power,
etc of unlicensed 2.4gHz transmitters, such as WiFi. You should check
them out. They vary from country to country.

If you have a ham license, then you can use 2.4gHz for data transmission,
but then you are restricted in transmission mode, encryption and data
content.

For example, the infamous Pringles can antenna was developed in the U.S. by
an FBI agent in the course of an investigation. It's use as a WiFi transmission
antenna is illegal in many places. The well pubicised long distance link in
Egypt was illegal.

Here in Israel we are limited to 100mW EIRP for civilian useage, except
for ham satellite operations which are limited to 25w.

BTW, there are limitations in the U.S. too, I just don't know them.

Geoff.

--
Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM
IL Voice: (07)-7424-1667 IL Fax: 972-2-648-1443 U.S. Voice: 1-215-821-1838
Visit my 'blog at http://geoffstechno.livejournal.com/

On Tue, 4 Jul 2006 11:03:49 -0400, Peter Pan wrote:
Can you help me roughly CALCULATE how to increase the range of my
home Internet wireless WiFi setup to a shed 300 feet away
....
I Had a linksys WRT54G in the house attached to my sat,
and used one of the 4 router outputs to daisy chain one to the wan input of
another WRT54G (same ssid) and a semi-directional antenna pointed towards
the garage about 500ft away,

Hi Peter Pan,

Oh my! Is "wireless" daisy chaining workable? Is it that easy?

I did not think I could just daisy chain multiple routers! Are you sure?
(My shed has no power but I think I could run an extension cord into it if
that would make things workable.)

Would I just set the second Linksys router (which, amazingly, has it's own
wikipedia entry at http://en.wikipedia.org/wiki/WRT54G) in the shed on the
same channel (SSID=12, name = default) as the first router in the house?

That is, could I put one linksys WRT54G in the house (perhaps with one
antenna replaced with a 7 dBd higher-gain directional antenna); and then
put the other Linksys WRT54G in the shed 300 feet away (perhaps with one of
it's antennas replaced with a similar 7 dBd directional antenna)?

Or, is it best to hardwire with cat5 the first router downstairs in the
house to the second router, say upstairs in the attic window pointing the
antenna toward the shed? I didn't even know that two routers could be daisy
chained. That might solve my dilemma.

Can someone confirm that two routers could be daisy chained either by wire
cat5 cable or by wireless signals as long as they use the same SSID channel
and network name? That solution seems to easy to be true ...

Beverly

On Tue, 04 Jul 2006 09:07:39 -0500, lid wrote:
Here is an easy way to hack your $60 wireless router into a $600
router (they use Linksys as the example):

Wow. I've never "modified" a router before but that is interesting that one
can increase the $75 Linksys WRT54G router
(http://en.wikipedia.org/wiki/WRT54G) RF output from 28 millwatts up to 251
milliwatts (http://tinyurl.com/lpk7w).

Being true to the original intent of this thread, how do I CALCULATE what
that does to my range?

Is this 9 dBd calculation of the modification roughly correct?
a) Power gain = Power2/Power1 = 251/28 milliwatts = 9x power gain
b) Range gain = sqrt(Power gain) = sqrt(9) = 3X range gain
c) Range = original range * range gain = 100 feet * 3 = 300 feet

Beverly

On Tue, 04 Jul 2006 11:48:12 +0100, Highland Ham wrote:

Beverly Erlebacher wrote:
Can you help me roughly CALCULATE how to increase the range of my home
Internet wireless WiFi setup to a shed 300 feet away from my house?

Presently, I can walk about half the way through the wooded area to the
shed with my laptop in hand before I lose the connection to the PCMCIA
802.11b,g Linksys card. Basically I need to gain 150 feet in "range".

But how?
================================================== ==
Having followed today's postings on this topic , I see that there is a
wooded area between your house and shed, hence there seems to be no free
line of sight between the house and the shed.
That's why it is difficult to calculate/predict the Gain you need to
penetrate the wooded area with a 2.4 GHz signal.

If you wish to use the laptop inside the shed at a fixed location it
MIGHT be good enough if you install a corner reflector yagi (High
Gain)antenna at both the house AND the shed. However then your laptop
needs a plug-in PCMCIA WiFi tansceiver with a connection for an external
antenna.
One of such units is the Make: Buffalo - Air Station Turbo G ,High Power
-unit which also has a built-in antenna.
Note : The coaxial cable between the 2 devices and their associated
antenna should be limited to only a few metres because of the high
frequency being 2.4GHz

Communication here is 2 way . Your laptop might receive the ( antenna
amplified) signal from your router located in the house ,but that does
not mean the router will receive the signal from the laptop without
additional facilities at the laptop.

Again , because of the probably partly obstructed path (wooded area) it
is difficult making any sensible calculations.

Frank GM0CSZ / KN6WH

Hi Highland Ham,

I see there are multiple solutions. Probably on the end of my list is
adding a wire to the laptop because then it wouldn't be wireless. Still,
it's an intriguing idea (I never knew laptops could have fixed antenna's
connected to them by wire).

If I do use two antennas, does that "add" the gain?

a) Antenna 1 transmits with a directional gain of, say 7 dBd
b) Antenna 2 receives with a directional gain of, say 7 dBd
c) Does that get me a 14 dBd overall gain?

Beverly

On Tue, 04 Jul 2006 06:11:27 -0700, Dan Richardsonk6mhe wrote:
If your goal is to increase your range then add an extender
(hams would prefer to call them repeaters).

Oh my. The seemingly perfect option.

I had come across the concept of wireless "repeaters" in my initial
googling before I went to the store, e.g., in this Microsoft "how to
increase range" article
http://www.microsoft.com/athome/more...elesstips.mspx and in this
"Extending WLAN Range" article
http://www.wi-fiplanet.com/tutorials...le.php/1571601

The repeater most often recommended was the "Linksys Wireless-G Range
Expander WRE54G".

However, I can't find that 802.11b,g WiFi repeater (aka range expander or
extender) anywhere in the local stores. The salesperson who sold me the
$300 USD 802.11n router and PCMCIA card combination said they didn't work
so they dropped it.

This solution seems to be the most elegant of all (but someone else
suggested just using a second router).

Can someone unconfusify the situation?

Is placing a repeater (on the same SSID) in the shed really the same as
adding a second router instead?

Beverly

On Tue, 04 Jul 2006 08:17:19 -0700, David wrote:
A "range extender" or "repeater" will cut the speed in half.

Hi David,

Interesting this speed difference. I'm worried about RANGE and all of a
sudden other factors come into play! Thank you for enlightening me. I know
more now than I ever did from you wonderful guys!

As I noted to someone else just now, I DID try to find the "Linksys
Wireless-G Range Expander WRE54G" WiFi repeater in the local stores but
they did not exist in any of the three stores I checked.

Also, some of the articles talk about an "access point"
(http://www.wi-fiplanet.com/tutorials...e.php/1571601).

Can someone tell me what part of my setup I would call the "access point"?

Beverly

On Tue, 04 Jul 2006 17:57:22 GMT, stephen wrote:
but - you mentioned you could run power out to your shed. Why not plumb it
in for power and networking?
then you can add a separate access point there and avoid antennae, gain,
loss through leaves and the rest.

Hi Stephen,
I'm confused about this "access point" thing.

Is that the same as a "router"?

Is it as simple as buying a second router (routers are familiar to me) and
just hooking that second router to the first router by cable and that would
extend my range by the distance of the cable connecting the two routers?

This is a key confusion point for me!
Beverly

Beverly Erlebacher wrote:
On Tue, 04 Jul 2006 08:17:19 -0700, David wrote:
A "range extender" or "repeater" will cut the speed in half.

Hi David,

Interesting this speed difference. I'm worried about RANGE and all of
a sudden other factors come into play! Thank you for enlightening me.
I know more now than I ever did from you wonderful guys!

As I noted to someone else just now, I DID try to find the "Linksys
Wireless-G Range Expander WRE54G" WiFi repeater in the local stores
but they did not exist in any of the three stores I checked.

Also, some of the articles talk about an "access point"
(http://www.wi-fiplanet.com/tutorials...e.php/1571601).

Can someone tell me what part of my setup I would call the "access point"?

The wireless part.

Beverly Erlebacher wrote:
On Tue, 04 Jul 2006 05:50:02 -0400, Rôgêr wrote:
Do folks here recommend the pringles cantenna or the pie tin
antenna for my 2-antenna router 802.11b,g directional application
where I need to also feed the computers within the house in
addition to the shed 300 feet away?

I use panel antennas almost exclusively, exceptions being some 24dbi
mesh antennas for backhaul.

Hi Rôgêr,

After reading all the articles posted, I now understand that:

a) The pringles can is hip; but it's the worst performer
http://www.oreillynet.com/cs/weblog/view/wlg/448
(it's not even metal foil lined and it's too small in diameter)

b) The coffee cantenna is more effective than the pringles cantenna
http://www.oreillynet.com/cs/user/view/wlg/1124

c) The dish antenna is the simplest of all and almost as good
http://www.freeantennas.com/projects/template
http://www.freeantennas.com/projects...te2/index.html

I also see, as Rod Speed so kindly noted, that the give and take is
that we lose range in some directions in favor of range in the
desired direction. Fair enough.

My one question is a practical one.

Why are there two antennas on my router anyway?

That gives a more reliable coverage than with one.

Is one transmit and the other receive?
Or are they both transmit and receive?

They're normally both transmit and receive.

Given I have TWO omnidirectional antennas on my wireless router,
if I put the parabolic dish antenna on one to direct it to my shed,
does that allow the OTHER antenna to radiate around the house
to handle the other computers roving around the house?

Yes.