Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4G...

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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?


 

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

Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On Mon, 30 Jul 2012 22:51:12 +0000 (UTC), "Vinny P."

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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.

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

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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?

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Yeah, much better.  Thanks.

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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.

--
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On Mon, 30 Jul 2012 22:45:30 -0700, Jeff Liebermann wrote:
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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.

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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.

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

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


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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

Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On Mon, 30 Jul 2012 22:45:30 -0700, Jeff Liebermann wrote:

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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.

Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On Wed, 1 Aug 2012 20:14:13 +0000 (UTC), "Vinny P."

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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.

--
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

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

Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On Wed, 01 Aug 2012 18:56:13 -0700, Mark wrote:

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That's exactly why we're looking at the noise levels.

One theory was that there was industrial, scientific and medical (ISM)
band interference.

Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On Thu, 2 Aug 2012 19:31:59 +0000 (UTC), "Vinny P."

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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?

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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.

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com jeffl@cruzio.com
# http://www.LearnByDestroying.com               AE6KS

Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On Wed, 01 Aug 2012 14:51:45 -0700, Jeff Liebermann wrote:

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Wow. Some of those noise levels are huge by way of comparison!
And the delta between average and peak were humongous on some!
For example: http://dl.ubnt.com/airview/airview-v1.1-beta_image01.jpg

I also noticed the 5GHz noise levels were lower than the 2.4 Ghz graphs
so I only looked at the 2.4 Ghz ones for comparison.

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I'd have to point it straight down to reach the wireless router in the
center of the house. :)

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That's probably the best idea yet. There is one problem though, as he has
his mounted on the top of a redwood - which is a pain to climb.

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I didn't realize the tool works on the laptop.
In my case, it's part of the software for the radio.

Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On Wed, 01 Aug 2012 14:51:45 -0700, Jeff Liebermann wrote:

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Wow. Some of those noise levels are huge by way of comparison!
And the delta between average and peak were humongous on some!
For example: http://dl.ubnt.com/airview/airview-v1.1-beta_image01.jpg

I also noticed the 5GHz noise levels were lower than the 2.4 Ghz graphs
so I only looked at the 2.4 Ghz ones for comparison.

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I'd have to point it straight down to reach the wireless router in the
center of the house. :)

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That's probably the best idea yet. There is one problem though, as he has
his mounted on the top of a redwood - which is a pain to climb.

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I didn't realize the tool works on the laptop.
In my case, it's part of the software for the radio.

Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On Thu, 2 Aug 2012 19:30:32 +0000 (UTC), "Vinny P."

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Must be fun to watch the signal level as the redwood sways, especially
near the top.  I did that many years ago with a 19dBi dish.  I
couldn't keep a stable signal.  We got lucky and found a "truncated"
redwood, with a clear view.  It was effectively half a redwood, but it
was stable.

I use a telescoping window washing pole for antenna tests.  Some ropes
on top to 3 cinder blocks is usually sufficient for a temporary mast.
Aiming it is a problem and does take some practice and profanity.

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I've never tried it before.  So, I downloaded the XP flavor and
immediately found that it doesn't work with the current Java 7.5
version.  So, I installed Java 6.0.33, which worked.  However, the
program complained that it didn't find the copy protection dongle
errr...  USB wireless device, that Ubiquiti sells for $40.  Since I
have a Wi-Spy, I really don't need yet another spectrum analyzer,
especially when the web page says it's "end-o-life".
<http://www.ubnt.com/airview


--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com jeffl@cruzio.com
# http://www.LearnByDestroying.com               AE6KS

Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On Mon, 30 Jul 2012 22:41:24 +0000 (UTC), "Vinny P."

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A couple of things look concerning. Wireless Mode is shown as Station
WDS. WDS, really? Is there no Client mode? The second thing is the use
of channel 5, which is a strange channel to use since it's not one of
the 3 completely non-interfering channels, (1, 6, 11).

You asked about noise, but all I see is a noise floor of -98dBm, which
looks excellent to me. You asked about noise on channel 12, which I
assume was a typo.

Regarding improving your reception, have you made sure the antenna is
properly aimed, both horizontally and vertically?


Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On Mon, 30 Jul 2012 18:16:19 -0500, Char Jackson wrote:
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Hmmm... the WISP told me to set it up that way.

The only options are:
a) Station
b) Station WDS
c) Access Point
d) Access Point WDS

Personally, I don't even know what WDS stands for.
But googling, I find this thread:
http://forum.ubnt.com/showthread.php?t=53297
Which says:
"WDS is always recommended if possible.
Sometimes it's not possible with other vendors,
since WDS is not astandard protocol. ...
Enabling WDS provides a true "transparent" layer 2 bridge."

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There's nothing 'called' client mode in the UBNT AirOS gui. :(

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I understand. That's the choice of my WISP.

Seems to me that channel 11 is better taking only the noise level here in
the Santa Cruz mountains into account.
 
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Thanks. I didn't know WHAT to look for!

Looking again at the spectrum analysis from the radio:

I see you're looking at the current (or average) noise (green line),
while I was looking at the peak noise (blue line).

There is about 20 dBm difference - so that's huge!

So, looking at the average noise (green), I see what you mean.

Noise is about -100 dBm at channel 1, peaks at -85 dBm at channel 2,
drops back to about -98 dBm for channel 3 through 8 (roughly), then it
peaks again at channel 9 to about -79 dBm, and then drops down to about
-100 dBm for the remaining channels 10, 11, and (yes), 12 before finally
dropping to about -108 dBm after that.

That's the kind of information I was looking for!
I didn't know what was a good or bad number, nor what to look at.


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Well, um, er.... there is a channel 12 on the spectrum analysis; so I
'was' talking about channel 12. Dunno if I can actually 'use' that
channel, but, it's there on the graph. (I have the export version of the
nanobridge.)
 
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I can visually see the access point, which is about 3 to 4 miles away, so
I first aimed the antenna by eye - and then aimed it using the built-in
signal strength aiming software which comes with Ubiquiti AirOS.

So, I 'think' it's aimed right! :)


Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On Tue, 31 Jul 2012 00:18:03 +0000 (UTC), "Vinny P."

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Then you may have to do it that way.

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Here's some more info on WDS:
<http://en.wikipedia.org/wiki/Wireless_distribution_system

The reason I don't like it is because it's an operational method that
retransmits some of what it receives, sort of like a repeater, and I'm
under the impression that doing so severely impacts throughput.

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I'm not too familiar with the Ubiquity UI, but I think Station is the
equivalent of what I called Client mode. Of course, if they want you
to use WDS, you're probably stuck doing so.

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Actually, I got the -98dBm from the UI snapshot that you provided, not
from the spectrum analysis screen.

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To me, a noise floor of -98dBm looks very good, but it's only half of
the equation. Equally important is your signal strength and how it
compares to that noise level. (Disclaimer: I don't know what I'm
talking about.)

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You won't be using channel 12 in the USA, so whatever noise is
occurring out there is of little or no concern.

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That's how I would have done it, as well. Eyeball it first, acquire
the connection, then while watching the real time signal strength
meter slowly swing it side to side until you're sure you've maximized
the signal strength. Note that the antenna may have one or more side
lobes that could potentially work for you, as well, depending on
whether you're staring at a huge source of interference when the
antenna is aimed directly at the WISP. Finally, if the antenna is
capable, adjust the antenna's vertical aim. Don't just eyeball that
axis, since some antennas have built-in downtilt that may not be
obvious. I don't know if that applies to the Nanobridge.

I'm at or beyond the edge of my knowledge, so hopefully someone who
actually knows will chime in.


Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On Mon, 30 Jul 2012 21:02:49 -0500, Char Jackson wrote:

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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?



Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On Tue, 31 Jul 2012 07:31:40 +0000 (UTC), "Vinny P."

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I would think that using the electronic alignment tool is better than
eyeballing it. That L-shaped mounting bracket looks more flimsy than I
was expecting, BTW. I think you said you were planning to replace it,
which sounds good to me.

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Sorry, no idea.


Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On Tue, 31 Jul 2012 09:20:28 -0500, Char Jackson wrote:

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The nanobridge, for about $70, comes with everything except cat5 cable &
the mounting arm.

It comes with the antenna, the mounting hardware, the power over Ethernet
supply (POE), and the transceiver.

I'm replacing the mounting arm with one from an old Dish TV antenna.

My only tactical problem is there is 'something' hard as steel in the
walls an inch under the stucco that I just can't drill through - so I'm
going to have to re-locate the antenna if I can't figure out how to get
through it.

Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On Tue, 31 Jul 2012 15:48:07 +0000 (UTC), "Vinny P."

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That should work.  Make sure it's screwed down tight and quite rigid.

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Stop!  You're drilling through a nail stopper.  If you keep going,
you'll end up going through a power cable.
<http://www.strongtie.com/products/connectors/ns-nsp-pspnz.asp

--
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

Re: Please help me interpret noise in the Santa Cruz mountains (roughly -75dBm across the 2.4GHz spectrum)
On 7/31/2012 9:12 AM, Jeff Liebermann wrote:
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Stopping is a good idea, but I don't think those Simpson Strong Ties are
THAT strong. Your supposed to think WTF and give up, but the poster has
dulled two bits! I think he is hitting something else.

BTW, would an antenna using a dish have significant lobes?

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