So given this scenario, would 2.4GHz be better?  I can use 5GHz inside the 
houses.

Rory

From: Af [mailto:[email protected]] On Behalf Of Chuck McCown
Sent: Wednesday, February 17, 2016 2:57 PM
To: [email protected]
Subject: Re: [AFMUG] Cambium 450i 900Mhz

I have not measured one, but if someone has a pine tree nearby and an ohm 
meter, measure the resistance of the needle.  Make sure you jam the probe into 
the interior of the thing.

I am guessing that the water content of the needle absorbs some of the RF 
energy al la a microwave oven.  But anecdotal evidence over the past 10-15 
years has shown that pine trees are worse than others so if the needle itself 
has a fairly low resistance, like 100 ohms, it is acting like a dipole with a 
termination resistor.  That is really going to suck up the signal.

Stealth aircraft have microwave absorbing foam on some of their surfaces that 
operate by similar principles.

From: Sean Heskett<mailto:[email protected]>
Sent: Wednesday, February 17, 2016 2:13 PM
To: [email protected]<mailto:[email protected]>
Subject: Re: [AFMUG] Cambium 450i 900Mhz

the wavelength of 900Mhz is ~33.3cm so a quarter wave length is ~8.33cm (~3 1/4 
inch).  Ponderosa pine needles (and many other pine needles) are around the 
same 3 1/4 inch length  https://en.wikipedia.org/wiki/Pinus_ponderosa

so with water in the needles you have a big 900Mhz RF scattering/reflector ;-)

-Sean


On Wed, Feb 17, 2016 at 1:47 PM, Sam Lambie 
<[email protected]<mailto:[email protected]>> wrote:
So if you have a minute to please explain how evergreen trees are terrible on 
900 mhz, I would greatly appreciate it.

On Wed, Feb 17, 2016 at 1:14 PM, Chuck McCown 
<[email protected]<mailto:[email protected]>> wrote:
Ponderosa?  Fir?  Cedar?

The length of the needles matter.

From: Rory Conaway<mailto:[email protected]>
Sent: Wednesday, February 17, 2016 12:51 PM
To: [email protected]<mailto:[email protected]>
Subject: [AFMUG] Cambium 450i 900Mhz

Realistically, what kind of distances do you get through these types of trees?


Rory Conaway • Triad Wireless • CEO
4226 S. 37th Street • Phoenix • AZ 85040
602-426-0542<tel:602-426-0542>
[email protected]<mailto:[email protected]>
www.triadwireless.net<http://www.triadwireless.net/>

“The ultimate measure of a man is not where he stands in moments of comfort or 
convenience, but where he stands at times of challenge or controversy” – Martin 
Luther King




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Sam Lambie
Taosnet Wireless Tech.
575-758-7598<tel:575-758-7598> Office
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