gwatts wrote:
Jeff wrote:

Note that in almost all places there are legal limitations on EIRP
(Effective Incident Radiated Power). In plain English, the more
you narrow a signal, the stronger it becomes.

Since you did not say where you are, I'll mention the two places I
know for sure. In the U.S. WiFi EIRP is limited to 1 watt for
mobile/portable use (e.g. laptops) and 4 watts for fixed links.



Bear in mind that 2.4GHz is also an amateur band where no erp limits
exist!!


Only 802.11b/g channels 1-6 fall in the amateur allocation of 2390-2450
MHz.

If operating under amateur regulations you must identify by CW, phone,
RTTY or TV image every 10 minutes or less (see 47CFR97.119), your
transmissions must be intended for reception by another licensed amateur
station or station authorized to communicate with amateur stations (see
47CFR97.111), that has to be the only reasonable way to effectively
communicate, no other radio service available that accomplishes the same
communications (see 47CFR97.113) and you have to use the lowest power
level capable of accomplishing the communications (see 47CFR97.313).

See http://www.access.gpo.gov/nara/cfr/w...7cfr97_01.html for
specific regulations.


I forgot to mention amateur communications cannot be encrypted, so no
https, see 47CFR97.113 again.

"gwatts" wrote in message
...
If operating under amateur regulations you must identify by CW, phone, RTTY
or TV image every 10 minutes or less (see 47CFR97.119)

Most amateurs set the SSID of the access point to their call sign, since this
is beaconed numerous times per minute. Apparently that's close enough to RTTY
to keep most people happy.

your transmissions must be intended for reception by another licensed
amateur station or station authorized to communicate with amateur stations
(see 47CFR97.111)

Sure.

that has to be the only reasonable way to effectively communicate, no other
radio service available that accomplishes the same communications (see
47CFR97.113)

This particular regulation creates plenty of argument, since realistically the
vast majority of activity on amateur radio frequencies these days could be
just as readily accomodated by either cell phones or the Internet; I doubt the
FCC has cited anyone for violating this rule for decades now.

and you have to use the lowest power level capable of accomplishing the
communications (see 47CFR97.313).

Indeed, although this too is subject to debate because people will argue that
while, e.g., 1W will get them a bit error rate of 10%, they "need" a near-zero
bit errorr rate and therefore transmit at 100W.

You point about not being able to use HTTPS or other encrypted protocols is
probably the most significant change in moving from using WiFi in an
unlicensed mode to using it under the amateur radio service's rules. However,
note that it is perfectly OK to obfuscate *authentication* data such as
passwords -- packet BBSes have done this for decades.

---Joel

"Jeff" wrote in
. com:

Bear in mind that 2.4GHz is also an amateur band where no erp limits
exist!!

Jeff


Not in most civilized countries.

2.4 Ghz is unlicensed, not unregulated.

On 7/25/07 10:12 AM, in article
, "Jeff"
wrote:


Note that in almost all places there are legal limitations on EIRP
(Effective Incident Radiated Power). In plain English, the more
you narrow a signal, the stronger it becomes.

Since you did not say where you are, I'll mention the two places I
know for sure. In the U.S. WiFi EIRP is limited to 1 watt for
mobile/portable use (e.g. laptops) and 4 watts for fixed links.

Bear in mind that 2.4GHz is also an amateur band where no erp limits exist!!

Jeff



Hams have a segment of it, but not 2.4 to 2.5.

However, if the wifi ends up in the ham band in a commercial purpose there
will be hell to pay when they get caught, ham or not.

Jeff wrote:
Note that in almost all places there are legal limitations on EIRP
(Effective Incident Radiated Power). In plain English, the more
you narrow a signal, the stronger it becomes.

Since you did not say where you are, I'll mention the two places I
know for sure. In the U.S. WiFi EIRP is limited to 1 watt for
mobile/portable use (e.g. laptops) and 4 watts for fixed links.


Bear in mind that 2.4GHz is also an amateur band where no erp limits exist!!

Jeff



Well.. not all the 802.11b/g channels are in the amateur band, and even
there, there is a power limit (transmitter output power, though, not
EIRP), so you could conceivably fire up your 1500 Watt transmitter into
a 20dBi antenna and blast away.

There is the other rule about minimum power needed for communication,
though.

" Well.. not all the 802.11b/g channels are in the amateur band, and even
there, there is a power limit (transmitter output power, though, not
EIRP), so you could conceivably fire up your 1500 Watt transmitter into a
20dBi antenna and blast away.


That is what the moonbounce operators do, but with more antenna gain!!

There is the other rule about minimum power needed for communication,
though.

Again moonbounce is not uncommon in the 13cms band.

Jeff

On Thu, 26 Jul 2007 09:13:02 +0100, Jeff wrote:

" Well.. not all the 802.11b/g channels are in the amateur band, and even
there, there is a power limit (transmitter output power, though, not
EIRP), so you could conceivably fire up your 1500 Watt transmitter into
a 20dBi antenna and blast away.

That is what the moonbounce operators do, but with more antenna gain!!

There is the other rule about minimum power needed for communication,
though.

Again moonbounce is not uncommon in the 13cms band.

Yikes! I was just doing a little calculating, and you could put a 20 dB
Yagi in your shirt pocket! =:-O

;-)
Rich
(OK, my shirts have big pockets... ;-) )

"amdx" wrote in message
...
Please see subject line-- Help, Wifi Antenna-- on
alt.binaires.schematics.electronic
for a picture of my concept.
Looking to combine Helical antenna and Wifi adapter card in one unit.
My experience is limited to MW bcb. I know there are many pitfalls at
2.4Ghz, so I'm looking for feedback on how to do this properly.
I'm using the following page as my guide.
http://www.wlan.org.uk/jhecker.html

This is to extend the range of my laptop computer.

Mike

Hi Mike

You sure find some great information on the Web.

I consider this article Jason Hecker publishes
http://www.wlan.org.uk/jhecker.html to be ALL the instructions anyone
would need for constructing a 20 dB directivity WiFi antenna. I am looking
for some feedback from you on its performance.

If you plan to investigate basic effects of changing size and shape of
Helix antennas, EZNEC sure makes Helix antenna investigation easy.

I am just curious, what kind of coax and connectors are you using, and,
?how much coax?.

Jerry

"Jerry Martes" wrote in message
news:KGKpi.5345$Da.3887@trnddc07...

"amdx" wrote in message
...
Please see subject line-- Help, Wifi Antenna-- on
alt.binaires.schematics.electronic
for a picture of my concept.
Looking to combine Helical antenna and Wifi adapter card in one unit.
My experience is limited to MW bcb. I know there are many pitfalls at
2.4Ghz, so I'm looking for feedback on how to do this properly.
I'm using the following page as my guide.
http://www.wlan.org.uk/jhecker.html

This is to extend the range of my laptop computer.

Mike

Hi Mike

You sure find some great information on the Web.

I consider this article Jason Hecker publishes
http://www.wlan.org.uk/jhecker.html to be ALL the instructions anyone
would need for constructing a 20 dB directivity WiFi antenna. I am
looking for some feedback from you on its performance.

If you plan to investigate basic effects of changing size and shape of
Helix antennas, EZNEC sure makes Helix antenna investigation easy.

I am just curious, what kind of coax and connectors are you using, and,
?how much coax?.

Jerry
Hi Jerry, Please review the picture I posted on
alt.binaires.schematics.electronic
in it you will see I'm trying to avoid connectors and cable carrying 2.4Ghz
R.F.
Thanks for being the only poster to have anything near a response to my
post.
Mike

"mike" writes:

Hi Jerry, Please review the picture I posted on
alt.binaires.schematics.electronic
in it you will see I'm trying to avoid connectors and cable carrying 2.4Ghz
R.F.
Thanks for being the only poster to have anything near a response to my
post.

Do note that many people's Usenet servers do not carry any binaries
groups, so they will be unable to look at your picture. If you were to
place the photo on a server where it can be accessed by HTTP or FTP,
these people would be able to get it. Many ISPs provide some web space
served by their own web server, and there are free photo hosting sites
like flickr.

Dave