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Re: Just curious how far your Wi-Fi access point is from your desktop computer
On Mon, 14 Oct 2019 12:44:29 -0700, Johann Beretta
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More like 46 to 57 feet antenna elevation for 80-100% Fresnel zone
clearance.  Plug in 6 miles for the distance and 2.4 GHz for the
That also applies to objects along the line of sight, such as trees,
hills, buildings, towers, phone poles, and other obstructions.

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: Just curious how far your Wi-Fi access point is from your desktop computer
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On 10/14/19 11:50 PM, Jeff Liebermann wrote:
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You only need 60% clearance to achieve full speed. My fresnel calculator
says 56 feet for 2.4 GHz and 60% of 56 is 33.6. I was a bit off,
admittedly, but I was in the ballpark for an off-the-cuff estimate.

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Re: Just curious how far your Wi-Fi access point is from your desktop computer
On Mon, 14 Oct 2019 23:50:03 -0700, Jeff Liebermann wrote:

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Hi Jeff,

You're aware we've been fumbling about this WISP stuff on our side of the
hill for years (not as long as you, but still years), where, we started
with Hughes, then Verizon (now Frontier, I think), then Surfnet, and
Hilltop, Ridge, Cooper, ViaSat, etc., you name it, we've tried it.

Since it's a neighborhood effort, we've been learning on our own.
o Mostly from failures - but we've had some good success also.

As such, you're likely aware, if you remember, we started with Mikrotik:
Then we went to bullets, which were infinitely more malleable:
Then the problematic nanobeams and the more reliable powerbeams
Then, the vastly more satisfying 2.4 GHz rockets:
And finally, for the most part, we've settled on 5GHz rockets:

Using the spare equipment from all the mistakes, sort of like this:

Given that progression of mistakes, my current access point, for the
Internet itself, has pretty good numbers of around 55 decibels (let's not
quibble about the type or sign) with a clear view of the similarly setup
access point miles away as shown in this screenshot below:

Where those numbers can be obtained by any user who has the line of sight
necessary (as always) who also has the same equipment on the other side.

The main advantage though, of this thread, is to ascertain how far can
people connect, line of sight, when they only have this equipment on one

To that end, my fundamental question, where I'd love to learn more from
people like you and Johann who seem to know a LOT more than most people
here, is what distances do you think are possible (assuming wholly
unobstructed views and sufficient heights to clear the primary Fresnel
Zone) for:
a. A laptop or desktop that has Ethernet  
b. With AC power always assumed to be nearby (for the POE & desktop)
c. With one of these antennas
With the Ethernet port set up sort of like this:

Given ideal conditions (which pretty much exist where I live), how far do
you think we could reasonably connect if we only had this equipment on one
end, where, of course, the other end matters.  

Let's assume the other end is, oh, I don't know, a typical SOHO WiFi router
(what's that ... something like ... oh, maybe 18 decibels ... where I know
and remember that you've studied this stuff and they lie in the specs - so
we could simply assume whatever you think is the "real" EIRP obtained.

In summary, under ideal conditions, with, oh, say, a Rocket M5 as shown
above, how far do you think a laptop/desktop could connect to a decent SOHO
WiFI router line of sight (with the primary Fresnel Zone assumed clear).

PS: Did you get hit with the PG&E power outage this week?
I filed a formal complaint with the CPUC that PG&E was playing games.

Re: Just curious how far your Wi-Fi access point is from your desktop computer
On Thu, 17 Oct 2019 21:20:27 -0400, Paul wrote:

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Hi Paul,

In summary, all pjp needs is to be able to "see" each antenna.

I agree you can go pretty far line of sight, as you just shared with us,
where I happen to live on a mountain surrounding Silicon Valley, where I
can likely see for more than 20, maybe 30 or more miles in some directions,
but only five or ten miles in others.

At WiFi frequencies, the distance pjp can attain will depend on how "clear"
his line of sight path is from the home to the RV.

If he can "see" the antenna, then, in our experience, the obstructions in
the Fresnel Zone aren't going to kill his signal, as long as he chooses a
powerful enough setup.

In the clear, I doubt there is a single Ubiquiti CPE radio that wouldn't
treat 1 kilometer as child's play though. A kilometer is nothing for WiFi.

What pjp needs, mainly, is simply the following:
a. A radio at his house that can see the radio at his RV.
b. A radio at his RV that can see the radio at the house.

I didn't think of this, until you brought up distances, but pjp doesn't
really even need AC power at the RV since these radios are about as
flexible as anything on this planet when it comes to power supplies.

They're usually able to handle from about 12 VDC to about 24 VDC at about 1
amp to 2 amps peak, which, if pjp only wants the radio working when he's
literally sitting in the RV, he can do by mooching off the RV battery.

I haven't ever needed to do that; but it sure seems possible (and, if not,
one of the folks on this ng will be glad to ream me with facts).

The main requirement pjp needs is each radio has to each the other.
o The radios are about $100 (give or take) depending on the radio

For example: <https://www.ui.com/products/
o Bullet <https://www.ui.com/airmax/bullet-ac/
o LiteBeam <https://www.ui.com/airmax/litebeam-ac-gen2/
o NanoBeam <https://www.ui.com/airmax/nanobeam-ac-gen2/
o PowerBeam <https://www.ui.com/airmax/powerbeam-ac-gen2/

I've never used them, but maybe these "nanostation" pairs would work:

They're designed to mount with "no tools" (or so they say).

Re: Just curious how far your Wi-Fi access point is from your desktop computer
On Fri, 18 Oct 2019 05:19:14 -0000 (UTC), Arlen _G_ Holder

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  If the system/signal is circular polarized, the Fresnel  
  zone will have no effect, because a deflected circular  
  polarized signal changes rotation upon deflection and the  
  result is to become virtually invisible to the receiver,  
  regardless of whether it arrives in phase or out of phase.  
  For example, a RHCP signal that hits a street, or a wall,  
  or anything else, then becomes a LHCP signal, and is  
  therefore invisible to the RHCP receiving antenna, regardless  
  of whether it arrives at the receiver in-phase or out-of-phase.  

In other words, if you happen to be using circular (or at least
elliptical) polarization on your link, you can forget about the
Fresnel Zone.  Most Wi-Fi hardware uses linear (vertical and
horizontal) polarization.  With linear polarization, the problem is
that at various radii from the direct line of sight, the direct signal
cancels with a reflected wave, forming "rings" of high and low signal
levels.  The rings with no signal or total cancellation are where the
reflected path is some multiple of 1/2 wavelength longer than the
incident path.  This does NOT happen with circular polarization, where
the polarization changes "sense", where the polarization changed from
(for example) RHCP to LHCP when reflected.  The receive antenna "sees"
both the incident RHCP wave, as well as the LHCP reflected wave.
However, since the receive antenna cannot hear the wrong "sense", it
only "sees" the incident RHCP wave and no cancellation occurs.  So, if
you want to build a link that isn't ruined by Fresnel Zone effects,
think circular polarization.

Also, if your path goes from a mountain top, to ground level in a
valley, and you have to deal with a temperature inversion layer,
chances are good that when the inversion layer is particularly
noticeable and at some specific altitude, the signal will disappear
for a while when it decides to wander off along the inversion line.
You might be able to visually see the other end of the link, but can't
get a decent RF signal along the same path.

Also, please consider the effects of fade margin or system operating
margin.  This is how much stronger the signal happens to be than some
reference level, usually somewhere near a minimum usable signal level
or BER (bit error rate).  This fade margin statistically translates to
the amount of time per year your link will be down.
    SOM      Reliability     Downtime
     dB        Percent       per year
      8         90           876   hrs
     18         99            88   hrs
     28         99.9           8.8 hrs
     38         99.99         53   mins
     48         99.999         5.3 mins
     58         99.9999       32   secs
For wi-fi, I like 20dB as a good but arbitrary fade margin for

Lastly, the various link calculations and data sheet specifications
tend to be for the BEST case situation.  In other words, reality sucks
and your results will follow accordingly.  Whatever happens along the
path, environment, or with the equipment, will ALWAYS increase losses
and decrease range.  I can post (for find in the Usenet archives) how
I do a link calculation if anyone wants it.

Note:  I had some surgery Monday, am recovering normally, but feeling
lousy.  I need some time to recover.  Please forgive me if I don't
reply to questions and comments immediately.

Bah Humbug(tm).
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: Just curious how far your Wi-Fi access point is from your desktop computer
On Fri, 18 Oct 2019 08:26:47 -0700, Jeff Liebermann wrote:

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Hi Jeff,

I hope you feel better.  

Thanks for the details on the Fresnel Zone calculations.
o Obviously all our stuff is typical Ubiquiti CPE

We often push through foliage, but, of course, we prefer not to.
o And even then, only for short distances or sparse foliage

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It's nice to know that the polarizations matter.

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We're only using Ubiquiti (& some old Surfnet Mikrotik) wifi CPE stuff.

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This "inversion layer" may be why some paths, which are about the same in
length (all less than ten miles for example), have vastly different signal
strength using the same rooftop devices to the same source access point.

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In my situation, I'm only about 6 miles from the WiFi AP, where I generally
get about -55 dBm on a Rocket M5 which, for me, is good enough.

It's mountain top to mountain top, so I'm not sure "if" an inversion layer
is involved, as the heights are within a thousand feet or so of each other.

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I don't profess to understand this stuff like you and Johann Beretta do,
but what I "think" you're calling the fade margin is what I colloquially
refer to as the "headroom", which is that I strive for a dozen decibels
above what works.

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I'll take 20 decibels above a working signal any day!

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On this, I fully agree with you, in that, for example, the nanobridge M2
"should" work, and 'does' work, but for various degrees of "work".

When we went from the NanoBridge M2 to the NanoBeam M2, all of a sudden,
with no other change, we got 3 to 8 decibels better signal strength. Who
knows why or how.

Then, over time, we went to the much bigger Rockets, where we progressed
from the M2 to the M5 due to noise considerations, where, at the moment, at
about 6 miles distance for our WiFi access point, the Rocket M5 with a 34
dBi dish (maybe it's a 30 dBi dish?), our signal is fine at around -50 dBm
with good quality metrics and noise floors around 104dBm (as I recall).

Heck, since I feel uncomfortable guessing, let me log into the rooftop
radio and take a peek (I hate that "certificate error" we get every time)
o Signal strength = -56 dBM (chain0/chain1 -58/-59dBm
o Noise Floor = -104 dBm
o Transmit CCQ = 76.5%
o TX/RX Rate = 144.444 Mbps / 144.444 Mbps
o airMAX = enabled
o airMAX Quality = 97%
o airMAX Capacity = 75%

That has no problem using a WiFi access point about 5 to 6 miles away.

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I looked up a few articles on how far people push through foliage.

Here's the first hit explaining that "it's complex":
  "foliage attenuation is a function of a multitude of parameters,
including frequency, foliage depth, tree types, foliage thickness, leaf
density, leaf size, branches, trunks, humidity, wind speed, height of the
tree relative to the antenna heights, path length through foliage, etc."

Lots of forum threads talk about WiFi penetration of foliage:
o Effect of Wind on Foliage Obstructed Line-of-Sight Channel at 2.5 GHz
o Ubiquiti Nanostation M2 & M5 penetration of 1.1km and 7 treetops
o 500 meters of foliage
o Networking over 0.5km with trees in line of sight
o How severe is the attenuation of trees?
o 2.5 KM link(right tools) through trees
o High throughput foliage penetration
o Outdoor wifi through wooded area
o Device Selection for Tree Penetration?  
o Another 5ghz trees question
o Best Wi-Fi frequency for penetrating woods
o 2 kilometers with 500 meters of forest in between
o How much signal do Trees block?
o Non line of sight (NLOS) considerations for wireless  
o Any Ubiquiti equipment able to punch through trees?
o WiFi to gate camera through trees
o Ubiquiti Nanobeam for Point-to-Point wireless through some trees?
o Long range (1000') outdoor WiFi connection transmission question
o Does *anything* work through trees ?
o Need to make a link over tree covered terrain
o WISP and the love of Trees and Rural

In the end, we just pop up a radio on each end and try it out.

We check signal strength, and, if it's good, we leave it working.
If not, then we deal with changing things around.

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Please get better.  

You've helped advise us many times over the years, which we appreciate.

If only the trolls would disappear, Usenet would be a lot more valuable.

Asking questions & sharing useful information on Usenet for decades.

Re: Just curious how far your Wi-Fi access point is from your desktop computer
On 10/20/2019 10:38 PM, Arlen _G_ Holder wrote:
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PerhSps they would if you STFU about them/  Maybe it is self inflicted.

Re: Just curious how far your Wi-Fi access point is from your desktop computer
It seems that  recently said:  

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Jeeez. You dont realize you are the trolls that should stfu you idiots.

Re: Just curious how far your Wi-Fi access point is from your desktop computer
On 10/21/2019 1:35 PM, Elder Jones wrote:
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If Arlen stops his silly stuff I'd stop too.  He has to show his  
superiority.  Just as you had to reply.  See how it works.

Re: Just curious how far your Wi-Fi access point is from your desktop computer

Given this was my WiFi & cellular test situation at various locations:
o abdelrahman.wifianalyzerpro <https://i.postimg.cc/NMbNGBnm/wifi01.jpg
o uk.co.soapysoft.wifianalyzer <https://i.postimg.cc/281Hmp7L/wifi02.jpg
o com.keuwl.wifi <https://i.postimg.cc/Ls3Dvm2w/wifi03.jpg
o make.more.r2d2.cellular_z <https://i.postimg.cc/tJwN7TNZ/wifi04.jpg
I ended up purchasing this setup to test out, which just arrived:
o <https://i.postimg.cc/7L910XNy/wifi05.jpg

Re: Just curious how far your Wi-Fi access point is from your desktop computer
On Mon, 21 Oct 2019 17:49:58 -0000 (UTC), Dan Purgert wrote:

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Hi Dan Purgert,

The useful takeaway is that we can fix our WiFi range by miles.

o On the outside, it's called a "nanobeam"
o On the inside, it's called a "powerbeam"
o And, the dish is steel.

o Moving forward, I'll call it a "powerbeam"

In that photo above, you can use just the horn to extend your range by
bridging your laptop Ethernet to WiFi, without much fuss as it's light

Essentially, you set up the router software & then you can plug that
powerbeam horn into any Ethernet ready laptop or desktop to vastly extend
the WiFi range. Except for price, this beats a USB dongle (IMHO), where
it's certainly no more costly than adding a repeater would be.

You can use the laptop with both horn & dish, but it's gonna be bigger.

The useful takeaway is that we can extend our WiFi range by miles.

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I have no problem naming the device formerly known as a nanobeam as a  "powerbeam".
o I was never one to quibble about such semantic things anyway

It's the trolls who can only quibble about such things that cloud the
otherwise adult technical valuable conversations on Usenet.

Back to JP Gilliver's question and to pjp's question
o I think any of the suggested Ubiquiti WiFi devices will work.

A LOS kilometer is puny for WiFi with these things, is it not?

Since we're trying to repair his Internet signal, we need to know of pjp  
a. What country
b. What wind conditions

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Let's clarify a few things for the general observer of this thread on that.

1. Since we're discussing TWIN devices, this "5AC" idea is feasible.
2. However, the distances are puny where 802.11 LOS will work just fine.
3. Plus, "5AC" generally costs more, where it's not needed (IMHO).
4. And the setup requires, at least "slightly" more knowledge.
5. Worse, WiFi re-use, which I do all the time Dan, is not possible.

Bear in mind, once you have one of these devices, you find uses for them!

Simply because, at WiFi they are as powerful as you can possibly get.
The useful takeaway is that you can extend your WiFi range by miles.

Re: Just curious how far your Wi-Fi access point is from your desktop computer
On Sat, 19 Oct 2019 02:28:09 +0100, J. P. Gilliver (John) wrote:

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Hi J.P. Gilliver,

That might be a neat idea for pjp (and others) to explore.

Unfortunately, that link shows up "dead" when I just tried it:

Do you have a working link so we can take a look at it for pjp?
o What's important is the transmit power & antenna gain!

Also, does anyone know what COUNTRY pjp is in?

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Let's look at that antenna, where, I entered its description into Google:
o 2.4Ghz Wifi Antenna 25Dbi Rp Sma Outdoor Wireless Yagi Antenna Directional B S2P
Which found it for $18 at Amazon:

To see what my favorite distributor, Streakwave, sells like it:

And $14 at Walmart:

Where this has a nice photo of the connector, which seems to be, on first
inspection, to be an "N-connector" (like those the bullets have):

Given you need to reduce losses when connecting these things, the $75
"bullet" should plug right in, and that gives you 630mW of transmit power:

Note: You do NOT want to be futzing around with the connectors!
(You can lose decibels in just the connection, even when done right!)

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Hi John,
You have to consider that the user doesn't TOUCH the RF cabling.

The "cable" for RF is always as short as it can possibly be.
o Notice there is ZERO cable in my powerbeams, for example.
o And notice my bullet attached to a planar antenna has zero cable

Your setup costs about the same as my setup pictured above does.
o Depending on how much your radio costs, of course

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The wind is NOT a problem for any of these dish antennas properly mounted.
o Neither is the rain.

I wouldn't choose my antenna based on worrying about what won't happen.
o I'd choose the antenna based on gain and location

I'd also diligently MATCH the RF connector!

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The USB dongle "might" be a good idea
o But your link didn't work for me.

Do you have a description of it?
o Particularly the transmit power & antenna gain

When Usenet works like it should, adults share valueable information.

Re: Just curious how far your Wi-Fi access point is from your desktop computer
On Sat, 19 Oct 2019 02:18:54 -0000 (UTC), Dan Purgert wrote:

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Hi Dan,

I like JP Gilliver's suggestion to use less expensive equipment than the
$100 PowerBeams I'm suggesting that pjp use to throw his WiFi from his
house to a puny 1 kilometer away - where JP's link was dead so we don't yet
know the transmit power of the suggested radio.

But on the antenna connections, I wouldn't suggest extending the length.

o Remember I asked the group WHY my $75 bullet had zero Rf cable?

It's the same reason my $100 PowerBeam also has zero RF cable:

About six inches is the longest RF cable I have, in my $150 rockets, Dan:

There is a really good REASON the RF coax is short to nonexistent, Dan.
o Paul already said why, when I asked him why this is the case.

When you need distance by wire, you use cat5 cable.
o It's what I've seen all the professionals do.

The only thing pjp needs to do with the RF coax is MATCH the connector.
o Everything else is done with cat5 cable.

I like John's idea of less expensive equipment - but we don't yet know the
cost or power of the suggested "USB" radio transmitter so we can't do a
comparison yet for pjp.

Usenet is a potluck where people from all backgrounds mix & share ideas.

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