About a year ago I posted a topic because the noise floor on 900mhz had literally gone to hell overnight. After investigating it disappeared as strangely and abruptly as it appeared.

Recently I started having some problems with a couple of my far out customers. I discounted it to trees growing - it is that time of year.

Then I started noticing very high re-regs on my good customers - customers with signals in the -60’s.

So, tonight I turned my AP in SM mode and wada the spectrum is trashed again.

Well experience taught me to set the color code in my AP turned SM to 0 and look at the AP Eval.

Truth is ugly and this is no exception.

What was perfectly clean spectrum up until a few weeks ago now has 4 other Canopy AP’s showing up.

I have a sneaking suspicion of who it is. Unfortunately my efforts to contact them about frequency coordination in the past have gone unanswered and ignored.

So, I have two questions.

1. How close to these AP’s need to be for me to be picking them up at this high a signal. My AP is a 8dBi HPOL Omni at 278’ AGL.
AP1 906mhz -74
AP2 924mhz -73
AP3 915mhz -69
AP4 924mhz -75

2. Once I find out who the company is interfering with my equipment, assuming they won’t cooperate, short of the normal sending them letters, etc. is there anything I can do to deal with the interference? At this location sectorizing is not an option. ... php?t=5342

At those signal strengths any idea how close they would have to be? Unfortunately with using an Omni I’ve got no idea which direction to even drive in…

I’m assuming within 10 miles?

you could check the AP evals of the SM’s and see if these other AP’s have popped up in there. may give you an idea of a location to start looking. ... ght=#19227
jwcn wrote:
At those signal strengths any idea how close they would have to be? Unfortunately with using an Omni I've got no idea which direction to even drive in...

I'm assuming within 10 miles?

Assume they are putting out 36dbm EIRP.
You are receiving them at -69dbm.
I'm going to assume an 8dbi antenna on your end.

36dbm + 69dbm + 8dbi = 113dbm

10 miles is 115dbm free space loss at 900Mhz....

So, yeah, 10 miles is not unrealistic, or even further - especially if they are over the 36dbm limit and/or your antenna is over 8 dbi.


Boys and Girls,

This is why they teach you to not run your 900mhz equipment above 150’.

We isolated the interference. Bay Broadband (Forum poster VLAN1) is running 3 120* HPOL Sectors that match the criteria based on the frequencies, color codes and SM counts.

Get this, their tower is 28 miles from mine. They are running at 200’

They are being extremely cooperative and have raised some valid questions about sync. I have my own questions about sync which I plan to post as a separate topic.

hahah yea…28 miles…pretty insane eh…i never would have guessed.