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Old March 30th 04, 02:49 AM
Dave Platt
 
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Should I be concerned about this setup:

Netgear AP Netgear Bridge YDI DC Injector YDI 500 milliwatt amp
Huber+Suhner planer antenna, model SPA 2400/85/17/0/V


I need the special antenna to overcome triple pane uv glass and 1 mile
to wisp.

The antenna is directional (85 degree horizontal) and my desk is right
behind the antenna. I use the set up a couple of hours a day.
Anything to be concerned about?


Well, you've got a 27 dBm radio, connected to a 17 dBi antenna. As I
read the Part 15 rules, that's just a hair over the legal limit for a
point-to-point 802.11b link - a 27 dBm radio is limited to a 15 dBi
directional antenna.

I haven't tried to do the calculations to see whether this level of RF
power is likely to be exposing you to RF levels which exceed the FCC's
human-exposure standards. I'm guessing that a lot of the power you're
transmitting is ending up bouncing off of the glass (secondary guess
is that this glass has a metallized coating?) and may be scattering
around the room.

If I were setting up a system of this sort I'd probably try to arrange
to put the antenna outdoors, and get by with a lesser amount of
transmitted power.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
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