[HamWAN PSDR] VOTE: 900MHz service experiment

Bart Kus me at bartk.us
Fri Mar 6 10:38:16 PST 2015


Hello,

5.9GHz is awesome when it works.  The speeds are great, and it carries 
as far as the eye can see with very low ambient noise floor.  It does 
however have problems when it needs to penetrate trees and buildings.  
To alleviate this, I'd like HamWAN to offer a slower but deeper 
penetrating 900MHz service.  900MHz is the lowest frequency ham band 
without bandwidth or modulation rate restrictions.  Before we deploy a 
full cell site, I'd like to get some real-world experience with 900MHz 
penetration, propagation and ambient noise conditions.  Here's the 
cheapest appropriate hardware we can use for this:

1x Vpol omni antenna @ $79.50/ea = $79.50 
(http://www.balticnetworks.com/laird-antenna-omni-8dbi-900mhz-n-female-integrated.html)
2x 9HPn modem @ $108.00/ea = $216.00 
(http://www.balticnetworks.com/mikrotik-metal-9hpn.html)
1x Shipping @ $UNKNOWN (quote not showing?!  Need to call them.) = 
$40.00 ???

Total: $335.50

I already have a 900MHz high gain Yagi-Uda in my inventory and can use 
that to do various field tests.  These can be directly compared against 
5.9GHz performance since the gear will be deployed to one of our 
existing 5.9GHz cell sites.  The results of such comparisons will give 
us a good idea of how well 900MHz might do for HamWAN.

Disclaimer: These may not be the right modems or antennas for us 
long-term.  A real deployment might use Ubiquiti Rocket M900 with their 
sector antennas.  These Ubiquiti items are far more expensive though, 
and their software doesn't integrate as easily into our network, so for 
the purposes of the test I believe the set of hardware I proposed will 
do well at deploying fast and keeping costs down.

NOTE: If both the votes are approved, I will combine shipping from 
Baltic to save money.

--Bart



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