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Old January 15th 06, 05:20 PM posted to rec.radio.amateur.antenna
Richard Clark
 
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Default Homemade Antenna Tower

On 15 Jan 2006 08:38:41 -0800, "Tekmanx" wrote:

Also, I heard 802.11g sucks outdoors. This true? And would you guys say
my 400mw radio is overkill for 4-10mile shot?


Hi OM,

It, or any link, only sucks as a function of what is called multipath.
This means that reflections combine at the receiver to blur the
signal. For conventional modes this is at worst obnoxious. For
digital it can mean total bit loss. In all practicality it translates
to high BER (bit error rate) and low information bandwidth due to
repeated packets being needed. The solution is not more power because
the problem will still be the same, only louder (so to speak).

Instead, the receiver antenna should have the gain so as to exclude
the signals coming from other directions. This exclusion is a
property of antenna gain, it is like cupping your ear to hear better,
there is not more signal to be had, you are merely excluding
distractions and focusing what is available.

400 mW in the clear and visible to a receiver is more than enough.
Your second problem is that you may not have 400 mW at the end of the
transmission line, at the antenna, because of the enormous loss in the
line if it is very long. That has already been discussed by Bobē.

73's
Richard Clark, KB7QHC