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Re: [TowerTalk] Interference Problem

To: Dave NØRQ (lists) <n0rq-lists@sbcglobal.net>,<dhearn@ix.netcom.com>,"Towertalk@Contesting.Com" <towertalk@contesting.com>
Subject: Re: [TowerTalk] Interference Problem
From: "Cameron Crum" <ccrum@dot11net.com>
Date: Fri, 15 Oct 2004 23:08:59 -0500
List-post: <mailto:towertalk@contesting.com>
As one of these WISP's myself I can tell you that 30 miles will be a stretch even if you do have LOS from the top of your tower, unless they operating illegally or they are going to put an 8 ft dish on your tower which would also be illegal. Max output in the unlicensed 2.4 Ghz is 36 dBm point to multipoint. Even if they give you a dedicated link there is still a ration of antenna gain to power reduction they must follow making unlikely that a 30 mile link will work with any reliability if at all. I'd be more concerned with what they are going to put up and wheter or not it is operating under the part 15 rules or not.

Cameron
----- Original Message ----- From: "Dave NØRQ (lists)" <n0rq-lists@sbcglobal.net>
To: <dhearn@ix.netcom.com>; "Towertalk@Contesting.Com" <towertalk@contesting.com>
Sent: Friday, October 15, 2004 7:56 PM
Subject: Re: [TowerTalk] Interference Problem



Until just recently, I had a wireless ISP, using 2.4GHz 802.11.
The radio/antenna unit was mounted on the corner of my roof,
only 10' off the ground, to get a clear view of the ISP tower.
Overall, the system usually worked well.  However,
when transmitting on HF, sometimes 100w would block
my connection, but only for the duration of  the signal.
The data transfer restarted immediate after the HF signal
ceased, so no real harm done.  Often, though, I could
run 100w and still have internet traffic.  I never tried to
determine which bands, which antenna direction, or other
factors caused the biggest problem.

Running 1kw increased the likelihood of the problem.
My tower is about 60' from the corner of the house,
and the antennas are 50'+ above the 2.4G radio/antenna.

To summarize, yes, HF sometimes affected the 2.4G signal,
but it wasn't really a problem.

--
Dave NØRQ



----- Original Message ----- From: "daniel hearn" <dhearn@ix.netcom.com>
To: "Towertalk@Contesting.Com" <towertalk@contesting.com>; "Amps Reflector" <amps@contesting.com>
Sent: Friday, October 15, 2004 6:07 PM
Subject: [TowerTalk] Interference Problem



I live about 30 miles from a company which supplies high speed I net service
by RF link. The terrain is such that some height is required for the antenna
used with the system. They typically use either a slot type or a parabolic
reflector. A test is planned next Tuesday to see if satisfactory operation
can be achieved at my location by mounting their antenna on one of my
towers. My tallest tower is a 131 ft. motor driven UST crankup. The tower
has a 6 el. 20m yagi on it.I am concerned about possible problems from
having the ISP antenna in the RF field of the 20m beam. I also have other
yagis for other ham bands from 40 thru 10m on towers which are some 100 ft
away from the big tower. I am concerned about system performance as well as
the possibility of smoking the ISP electronics.
Has anyone had success using a rf linked ISP system with the antenna
mounted near a KW driven yagi? How near? If not, what would members of the
reflector think might happen in this case? What might be a reasonable number
for closest spacing. I am guessing that a usable signal might be found with
the antenna 20-30 feet below the 20m yagi.
All input appreciated, 73, Dan, N5AR



_______________________________________________


See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions and ask for Sherman, W2FLA.

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_______________________________________________


See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions and ask for Sherman, W2FLA.

_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

_______________________________________________


See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions and ask for Sherman, W2FLA.

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