I have several sites with KP 120's doing ABAB. A couple of the sites are
pretty close to each other and it was necessary to have one site using
906 and 924 and the other on 910 and 920. Non-colocated 4MHz carrier
offset doesn't always work, for example, one SM was seeing a 924 and a
920 sector on each site within 3dB, but we later found out that SM was
out of alignment. Actually it was perfectly aimed between both sites
because I think they were originally on a tower about 12 miles away in
that direction and when we turned up the new sites, they just worked so
nobody ever went out and aimed them properly.
The other thing with the KP 120's is, while they are nice compact
antennas with decent forward gain for the size, they don't have the
greatest F/B ratio. So SM Tx power control is a must. Luckily all of the
900 radios can do it. Til-Tek sectors perform great, but there was no
way in hell I'd ever be able to put four of them on say a 25G, too much
load.
When you're stuck with 900 as a last resort, you find ways to make
things work, and it's usually never pretty considering the limited
spectrum and horrible interference.
On 9/29/2014 10:35 AM, Ken Hohhof via Af wrote:
OK, thanks.
*From:* Shayne Lebrun via Af <mailto:af@afmug.com>
*Sent:* Monday, September 29, 2014 10:22 AM
*To:* af@afmug.com <mailto:af@afmug.com>
*Subject:* Re: [AFMUG] standard 900 MHz Canopy channels
906,915,924 are the way to go.
Properly synced Canopy needs no guardband. Properly synced ePMP needs
5mhz guardband. Unsynced anything technically needs
guardband=2*channelwidth.
*From:*Af [mailto:af-bounces+slebrun=muskoka....@afmug.com] *On Behalf
Of *CBB - Jay Fuller via Af
*Sent:* Sunday, September 28, 2014 3:08 PM
*To:* af@afmug.com
*Subject:* Re: [AFMUG] standard 900 MHz Canopy channels
would assume that would be doable, but that leaves no guard bands at all.
we run 906,915,924 and tell everyone else to do so as well...
----- Original Message -----
*From:*Ken Hohhof via Af <mailto:af@afmug.com>
*To:*af@afmug.com <mailto:af@afmug.com>
*Sent:*Sunday, September 28, 2014 12:18 PM
*Subject:*[AFMUG] standard 900 MHz Canopy channels
I have always assumed the standard channels are 906, 915 and 924.
But I keep getting competitors going on 906 and 922. I understand
they are
probably trying to avoid high power licensed stuff like paging
around 930.
But if I go on 915, I find it overlaps with 922 and bad juju ensues.
Especially when this is a newcomer and they have no subs yet and
don't match
your timing and don't care because ... they don't have subs yet
and aren't
suffering the effects of the interference. I have found that a hot
interferer on 922 will pretty much blow you off the air if you try
to use
915, unless the timing parameters match, even though that's only 1
MHz of
overlap.
So are the default channels actually 906, 914 and 922 in the real
world?
