Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)

I just switched to a new WISP in the Santa Cruz mountains and was told to install the Ubiquiti Nanobridge M2-18 Outdoor MIMO 2.4GHz 18DBI.
This new UBNT NB-2G18 comes with "AirView", which is apparently a new spectrum analyzer feature.
Looking to debug why my "Capacity" & "Quality" results are lower than a neighbor's with the same equipment and only slighly shorter LOS, here are my AirView result from a moment ago:
Note: The WISP is on a Rocket M2 + Rocketdish on channel 5 about 3.2 miles away, LOS.
My neighbor, 0.2 miles closer to the access point, has almost double the quality & capacity numbers, and 3dB better signal strength ... using the same equipment.
Here are my current readings:

My questions? Q1: Help interpreting noise in Santa Cruz would be appreciated ('specially by Jeff!). Q2: What can I do to improve capacity & quality? Q3: Why is there that much noise at channel 12 anyway?
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I belatedly realized the link I gave was lousy quality so here are the full-size images:

How would you interpret these results with respect to noise in the Santa Cruz mountains above Silicon Valley?
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On Mon, 30 Jul 2012 22:51:12 +0000 (UTC), "Vinny P."
Y'er noise level is about -95dBm. If everything else were perfect, that would be a really good noise level. However, I think you have other problems. There are only 2 signals visible on Ch 2 and Ch 9. From your lofty location, you should be picking up all kinds of junk, even with the directional antenna. Point the Nanostation at SCZ, San Jose, or Loma Prieta and see if it can hear more signals. If not, fix your radio, antenna, coax, etc.

Post a picture of your derangement. Most of the problems I find are not equipment problems. They're installation problems.

Because there's someone transmitting on Ch 12. -70dBm is not very strong. -30dBm would be a strong signal. A better question to ask is why don't you hear more signals?

Yeah, much better. Thanks.

Dunno. You have an 18dBi antenna, which should have a beamwidth of about 10 degrees. You'll hear plenty of junk if the antenna is pointed in the right direction, but none if it's to the side. If your Nanostation is pointed at the Hilltop (or is it SurfnetC) access point, you don't have anywhere near enough usable signal. Something is wrong with your setup.
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On Mon, 30 Jul 2012 22:45:30 -0700, Jeff Liebermann wrote:

Good idea. It's easiest to point to Loma Prieta or San Jose. I'm picking up an antenna mount from an old Dish TV antenna because the mount I have isn't sturdy enough for Santa Cruz winds - so when I set that up, I'll test the AirView for more signals like you suggest.

Here's a picture of the mount on the wall of the house near the roofline. I tried to drill through the wall but ran into the hardest steel plate you can imagine. Dulled two drill bits before I realized it was impenetrable.

You can see my first set of drill holes in this picture (to the right). What is it that is inside the wall, I'll never know.

When I replace the antenna mast, I'll run that test for you!

I think the spectrum analysis images of noise are really useful in general to anyone who has WiFi!

You know the mountains well. Rude Dave at Surfnet & Loren at Hilltop are out here as well, but my signals are from Mike at Ridgewireless.net who installed an AP recently to serve the mountain community.
These are the known ISP providers for the mountains that I know of (do you know of any others)? * Hughes Ku satellite * Viasat Exede Ka satellite * Surfnet WISP * Hilltop WISP * RidgeWireless WISP * Etheric WISP * Cooplabs (aka Superspeedy) WISP
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On Mon, 30 Jul 2012 21:02:49 -0500, Char Jackson wrote:

The antenna is on a cantilevered mounting arm screwed into the outside wall of the house under the roofline.

Note: I tried four times to drill deeper holes but there is a solid steel plate in that wall (apparently) that nothing can possibly dent. What is it, I don't know! ???
While the mounting arm can't be tilted - the antenna bracket has many degrees of tilt and rotation.
The problem is the tilt is hard to judge by eye so I did it by airOS as shown in the screenshot below:

BTW, I never understood transmit CCQ. Are these numbers OK?
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On Tue, 31 Jul 2012 07:31:40 +0000 (UTC), "Vinny P."

Looking at the data sheet, it appears that you're looking at about a 10 degree beamwidth: <http://www.ubnt.com/downloads/datasheets/nanobridgem/nbm_ds_web.pdf Take a protractor and a piece of paper and draw 10 degree angle. That's your alignment accuracy. Trying to bore sight aim that antenna is not going to work. You'll have to rock it back and forth to find the maximum signal point. From the screen shots you've posted, I don't think your antenna is aimed at their AP.
Looks like you have it mounted vertically polarized. Is that what RidgeWireless is using?

Probably a nail stopper protecting the area where Romex crossed over a 2x4. <http://www.strongtie.com/products/connectors/ns-nsp-pspnz.asp Consider yourself lucky that you didn't continue as you would eventually have drilled through a power line. Next time you drill, use a stud finder to find the stud, but also use an AC voltage detector to make sure you're not drilling into a power line.
Please remember that you have only one life to give for your connectivity.

Ummm... you're on AirMax ISP firmware 5.3.5. Version 5.5 is out. Ask your ISP before upgrading: <http://www.ubnt.com/download#NanoBridge:M2

Client Connection Quality. Basically, it's the ratio of how an ideal radio would be expected to act, divided by what you're really seeing. The Ubiquity definition is kinda vague. This is from Mikrotik and hopefully should apply to Ubiquiti.
Client Connection Quality (CCQ) is a value in percent that shows how effective the bandwidth is used regarding the theoretically maximum available bandwidth. CCQ is weighted average of values Tmin/Treal, that get calculated for every transmitted frame, where Tmin is time it would take to transmit given frame at highest rate with no retries and Treal is time it took to transmit frame in real life (taking into account necessary retries it took to transmit frame and transmit rate).
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Jeff Liebermann snipped-for-privacy@cruzio.com
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On Tue, 31 Jul 2012 08:51:18 -0700, Jeff Liebermann wrote:

Funny you should ask that.
I wasn't sure which way to mount it so I simply followed the instructions that came with the radio.
I do know the WISP has both polarities because he's the one that told me I was only using half the bandwidth with my Ubiquiti Airgrid - so gaining the other polarity is the whole reason for me buying the nanobridge.
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On Tue, 31 Jul 2012 08:51:18 -0700, Jeff Liebermann wrote:

:)
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On Tue, 31 Jul 2012 08:51:18 -0700, Jeff Liebermann wrote:

Hi Jeff,
Here's how my friend Simon explained it to me today ... so I hope to have more data this weekend.
... ... ... ... cut here ... ... ... ...
If you look at the antenna profile for the NanoBridge M2, it shows you how much loss to expect if you are a few degrees off target. If you are 15 degrees off-target, you lose about 7 dB.
15 degrees is a whole lot. The sun moves 15 degrees in an hour. Your thumb and fist (like a hitch-hiker's signal) at arm's length is 15 degrees.
At 5 degrees off-target, you lose 2dB. That's three fingers at arm's length. That is still quite a lot of miss. The entire mountain is 5 degrees across when looking at it from my house.
The sun and moon are each a half of a degree across. If you are off- target by the apparent width of the moon, or even twice that, you won't see a single dB of loss. The entire property where the antenna lies is about a degree wide as viewed from my house.
In other words, aiming is not your problem.
We see random fluctuations in signal strength that dwarf anything like a 5 degree aiming error.
I have the tripod, and a bunch of brand-new NanoBridges. You can ride along with me and we can set it up at different places along the road and see what kind of signal and speeds we get, with and without the power lines and towers in the way.
I'll be bringing it to Joe's house and Bill's house today or tomorrow, and you can help set them up if you like, and we can get measurements from those places as well.
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On Sat, 4 Aug 2012 02:46:35 +0000 (UTC), Vinny P. wrote:

I've yet to see anyone question the pattern/lobes/nulls of the _transmitter_.
Jonesy
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On Sat, 4 Aug 2012 02:46:35 +0000 (UTC), "Vinny P."

It's a bit more complexicated than that. Just because you can see the other end, doesn't mean that a 2.4GHz link will be reliable. Any objects inside the Fresnel zone will cause problems. Reflections off the ground will cause nulls and peaks. Moving objects (cars) close to the path can cause fades. I use Radio-Mobile software: <http://www.cplus.org/rmw/english1.html to produce path profiles like this: <
http://802.11junk.com/jeffl/coverage/K6BJ-to-KI6EH/K6BJ-to-KI6EH-Path-Profile-01.jpg
This one is at 420MHz and has some errors in the numbers, but gives a tolerable idea of what can be done. All you need to do is supply some numbers.
A simpler version is just the path loss. <http://wireless.navas.us/index.php?title=Wi-Fi#Link_Calculations that simply calculates the fade margin, which directly translates to reliability and uptime. I'm fairly sure you're close enough that there are no path loss issues. I'm not so sure about obstructions along the path.

6dB loss is the same as cutting your range in half at the same signal levels.
Another way to think about it is how much of your dish antenna can you cover in order to produce a -6dB loss? Well, covering half will be -3dB loss. Another half will be -6dB. So, how well does your dish work with a dish only 1/4th the size?

Probably true. Something else is wrong which might be indicative of defective equipment. The easy way to determine that is to compare with a similar piece of hardware.
Did you ever settle on vertical or horizontal polarization?

Random fluctuations as in fades and nulls is exactly what you get when there are multiple reflections and objects in the Fresnel zone.

Great idea. Do it.

Even better. Remove your Nanobridge and bring it along. Compare signal levels.
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It isn't the signal strength as much as the waveform fidelity. If you are off a bit, you get more reflections of the transmitted signal.
When I use a rather fat beamed antenna, I move it from side to side and note where the signal begins to drop. then pick a spot in the middle. This is something like direction finding, where null are easier to detect than peaks. In this case you aren't using the null, but rather you reach the edge of the main lobe and the signal falls off rapidly.
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Vinny P. wrote the following on 7/31/2012 3:31 AM (ET):

You probably hit a metal framing hanger (or framing metal hanger) in that first area.

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Bill
In Hamptonburgh, NY
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On Tue, 31 Jul 2012 12:40:14 -0400, willshak wrote:

Whatever it is, it's big because the two bracket holes are a good four inches apart, and I drilled four of them, about six or seven inches apart, so the impenetrable object is (at a minimum) four inches by six inches large.
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On Wed, 01 Aug 2012 18:58:32 -0700, miso wrote:

Four holes! Drilled about 4 inches apart up/down and about 6 or 7 inches apart side-to-side.
I can't imagine what it is - but there is no way my drill bits were making 'any' headway. I was on a ladder, so I couldn't use 'all' my strength, but I've drilled enough to know that I was hitting hard steel.
I didn't even see any metal chips coming out, although they could have been lost in the inch of stucco as I was pulling the bit out.
At the moment, I can only think that there is some kind of earthquake tie of some sort since I'm very near the fault line.

Looking at the Ubiquiti Nanobrdige M2-18 datasheet at: http://dl.ubnt.com/nbm2_datasheet.pdf
The lobes don't look too bad:

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On Mon, 30 Jul 2012 22:45:30 -0700, Jeff Liebermann wrote:

Hello Jeff,
In preparation to resite the antenna with a stronger bracket in a different location that doesn't have a steel plate in the wall, I just ran three noise level tests - one pointed at the city of San Jose, the other at cube at Mount Umunhum - and the third at Loma Prieta.
I set the preference on the top graph to 'show channel usage' (whatever that means). And I set the bottom graph to 'show more channels'.
Here is the noise level with the antenna pointed at San Jose:

Here is the noise level with the antenna pointed at Loma Prieta:

And here is the noise level with the antenna pointed at the cube:

All I can make out is that the noise to San Jose and to Mount Umunhum are about the same - while the noise to Loma Prieta is different.
I'm not sure what the AirView "channel usage" tells us - but they sure are 'perty graphs. It would be nice to see what everyone else is getting in their neighborhood by way of RF noise.
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On Wed, 1 Aug 2012 20:14:13 +0000 (UTC), "Vinny P."

Something is wrong. The signal levels are much too low. See sample photos at: <https://www.google.com/search?q=ubiquiti+airviewn&tbm=isch
You might try pointing it at a wireless router some place nearby. If it doesn't go nearly full scale, you have a sensitivity problem.
Also, you might try to drag your Nanostation over to the neighbor with a similar system, and point it at the same access point. That way, the signal levels should be the same. Then, compare AirView screen.
I just downloaded Airview 1.0.11 for my XP desktop. After installing, it won't start. I'll troubleshoot later.
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you do know that the 2.4GHz band is the ISM band and is used for microwave ovens among other things besides WiFi?
Mark
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On Wed, 01 Aug 2012 18:56:13 -0700, Mark wrote:

That's exactly why we're looking at the noise levels.
One theory was that there was industrial, scientific and medical (ISM) band interference.
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On Thu, 2 Aug 2012 19:31:59 +0000 (UTC), "Vinny P."

I was going to grind some numbers converting 1mw/cm^2 at 5cm max radiation leakage into what you would expect to see at various distances, but got sidetracked. Maybe later.
However, interference is not your problem. From the spectrum display, your receiver is comatose and can't hear either signal or interference. Got a warranty?

Pick an interference source, any interference source: <http://wireless.wikia.com/wiki/Wi-Fi#Interference I can add about 4 more sources that I've found recently. However, the ones that I keep running into that are giving me the most trouble are wireless streaming video, wireless security cameras, and wireless point to point telemetry.
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