Can you help me interpret this spectrum analysis noise plot?

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Danny D'Amico wrote:

If you rfeally hae to there iss no such thing as this the problem and this is solution. You need many hours "cut and try type approach". First off like using best cables you can get, even POE injectors are not created equal.
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On Sat, 21 Dec 2013 01:02:42 -0700, Tony Hwang wrote:

Hi Tony, With my cabling all less than 100 feet, it really doesn't matter what POE I use with my three radios.
My Bullet came with a half amp 15 volt POE, and my Nanobridge came with an amp 24 volt POE, and my Rocket came with an amp 24 volt POE with its own reset switch (which is really handy since the rocket is on the roof).
In practice, since my cabling is so short, the POE does not matter, as far as I can tell.
Something else *does* matter though ... :)
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A bigger dish will help. I was asking about the RF cable, not the Ethernet cable. I think what you want to do is read up on the subject. Here are some key words to search for info Noise figure G/t Link budget Path loss Thermal noise -174 dBm / Hz Noise bandwidth Spectrum analyzer noise measurements Parabolic reflector Beam width Aperture size Also it seems your real goal is to increase the data rate but you seem focused on the ex noise. Don't forget,the link needs to go both ways. Step one is to determine which path direction is your limiting factor. Have fun... Happy new year Mark
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On 12/20/2013 10:54 PM, Tony Hwang wrote:

Nonsense, when you quit learning you're dead. You know how to learn which is a quality many people lack. ^_^
TDD
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On Sat, 21 Dec 2013 05:35:03 -0800, makolber wrote:

The RF cable is as short as it can be, since the radio is clipped directly into its mount on the back of the dish.
RF line losses are as low as I can make them without additional shielding.
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On Thu, 19 Dec 2013 09:17:43 -0800, makolber wrote:

Hi Mark,
I *am* a bit concerned with the -88dBm noise level, but, I do agree with you that I have a high-gain antenna and high power transmitter with decent receive sensitivity.
What concerns me most about the -88dBm noise is that some of my neighbors, using the exact same equipment and connected to the same WISP AP, have 9 dB less noise!
Since every 3dB is doubling (or halving), I have 8 times the noise that they have! That's mostly what concerns me.
It would be nice if others on a.h.r listed their noise figures, so, we could take an informal survey.
My modem (actually it's a tranceiver, but, it's just like a modem) is where I measure all this noise.
Can you guys get noise figures out of a cable or DSL modem?
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Danny D. wrote:

How come you are using radio link. no cable access? You way out in boon dogs like my cabin? My only access is via satellite there. It costs a lot so I don't use it.
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On Thu, 19 Dec 2013 11:43:28 -0700, Tony Hwang wrote:

Hi Tony,
We are in mountains. Our roads are one-lane for miles on end. Zoning in our area is 40 acres, so, if you have 79 acres, you can only put one house on it (they don't want more people living in the mountains - they prefer them all squashed together in San Jose, which we can "see" (along with the smog above it).
Even though we're few and far between (we can't even see the neighbor's houses) but we all know each other better than if we lived in a city.
So we all know what the others have by way of Interner access. None of us can get DSL because we are something like 30,000 feet from some switching station that we need. It's too far.
None of us can get cable because the poles out here only have power and telephone. Nothing else is on them.
Luckily, we're high up, so, we have a fantastic view of the sky. Satellite is no problem. Out here, both Hughes and Viasat Exeed serve us. But, satellite, in a word, sucks, only because of bandwidth limits and latencies. Mostly the bandwidth limits. The speeds are actually pretty good. But, that bandwidth limit is a killer.
Of course, we could use cellular modems, but, there is a better solution for us. We use line-of-sight WiFi access points. Since we can see both sides of Silicon Valley, we could put an antenna up 30 miles away and see it easily by line of sight. In almost all directions.
The net is that we all have dish antennas bristling on our roofs. They point at the local access points.
We have only four WISPs to choose from (that I know of), so, each of us points to whatever WISP gives us the best deal.
Mine allows me to be unthrottled, which is great because I have no bandwidth limits and I have no speed limits. If I can get 30Mbps, that's what I get.
My first radio, a Bullet M2, only got about 8Mbps (symmetric). So I upgraded that to a Nanobridge M2, which got about 10Mbps. Now with the Rocket M2, I get almost 20Mbps.
So, our investment in radios has a direct relationship to our Internet speeds. Our "modem" is the radio (aka, the transceiver).
BTW, I'll ask you a question about you cabin in the next post ...
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On Thu, 19 Dec 2013 11:43:28 -0700, Tony Hwang wrote:

Hi Tony, Satellite is fast, but sucks due to bandwidth & latency reasons.
If your cabin can use WISP, that's what I suggest. What you need for WISP is line of sight to the access point.
From your cabin roof, can you *see* anywhere that does have cable Internet access?
If so, you can home-brew up a fast Internet access easily. Of course, there are *many* solutions, and the best is to find a WISP access point that you can visually see ... (which is what I do).
But, by way of example, let's say that 25 miles away, you can see a friend or relative who has cable access. Remember, you must *see* the area. Of course, even at about 3 miles, I can't actually pick out my WISP antenna, but, I can scan the area with binoculars enough to know I'm pointed roughly at it (at 3 miles, my 5 degree beam is 1200 feet wide in both horizontal and vertical directions).
At 25 miles, your beamwidth will be fine if you're anywhere pointed close.
Then what you do is buy a pair of radios that cost about $100 in total, plus another $100 (or so) for mounting equipment, and another $50 or so for cabling.
So, for roughly $250, one-time cost, you can establish a link that easily transmits that cable Internet access from the populated area to the rural area of your cabin.
The great news about that is the $250 is a one-time fee, so, if you divide that over it's useful life (10 years?), it's about $25 a year.
In summary, it's really easy to transmit WiFi from one place to another, with the huge caveat that you need line-of-sight between the two points. Hope this helps you with your cabin.
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On Thu, 19 Dec 2013 19:42:37 +0000, Danny D. wrote:

Just by way of another example, I can see all of San Jose, so, out of the million people down there, I could find one willing to beam their high-speed Internet to me, simply by adding a radio to their roof and to mine.
(In effect, that's what I do, except I'm paying my WISP to be that other antenna.)
The fact it's so easy and cheap (nowadays) to beam an Internet connection a dozen miles, makes me wonder why more people don't do it.
Of course, the caveat is (and always was) line of sight is needed, although not having LOS is easy to solve with repeaters.
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On 12/19/2013 10:30 AM, Jeff Liebermann wrote:

Here in Alabamastan we actually have a state college, The University of Auburn, which is both the premier agricultural and engineering school. I traveled to Auburn one year to visit some friends and drove past "The Swine Research Unit". The smell could gag a maggot but the pigs were happy. In the mid 1960's at The University of Alabama, I started playing with and learning a tiny bit of Basic and Fortran in order to play with the Univac which was on its way out and the new IBM 360/50 RAX system which was replacing it. Kids these days have no idea how user friendly computers are now compared to what I started playing with like the analog computer at my school but I really believe computers were more fun all those years ago. Now they're tools, not so exclusive anymore and any kids gaming computer has much more computing power than what was considered a super computer at one time. ^_^
TDD
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The Daring Dufas wrote:

You guys are little bit behind me, when I was into it during and after school, computers were called electronic calculator as such containing vacuum tubes, mechanical relays.. from there transistors, small scale IC all the way into nanotech which is now. I used to use blank punch card with columms and rows all half pre-punched so we can push the confetti out to make holes where we want to do Fortran programming. If you drop the card deck by accident, you have to resort one by one to make them in proper order before you can have it read. Also remember 51 column card? Credit card receipts were 51 column card size which could be read after they are punched by key punch operators(girls) reading the amount written and imprinted account number. My Ham radio hobby was from the '50s, licensed in '60. Hold Extra U.S., Advanced/Digital Canadian, First class Korean licenses. Right now I am busy resetting up our HT system into 7.1 with new AV receiver and speakers. Better be done before X-mas.
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On 12/19/2013 12:35 PM, Tony Hwang wrote:

We must pass our knowledge and skills on to a younger generation because they are being lost. If our modern society crashed, most people would be helpless because they have no idea how older simpler technology works. Perhaps Boy Scouts could help people survive? o_O
TDD
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On Thu, 19 Dec 2013 13:35:46 -0600, The Daring Dufas wrote:

I wonder if popsicle sticks, duct tape, and frozen orange juice container can still fix a modern cooling system leak!
:)
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On 12/19/2013 1:46 PM, Danny D. wrote:

20 years ago, I was working on the chilled water system at a bowling alley when a 10 year old kid walked up to the counter and asked the counterman if he could use the phone to call home. The fellow reached under the counter and set a rotary dial phone in front of the kid and the kid had no idea what he was looking at much less how to use it. ^_^
TDD
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The Daring Dufas wrote:

Add to that hay wire. Man's neck ties, woman's nylon stockings, LOL!
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On Wed, 18 Dec 2013 22:59:04 -0600, The Daring Dufas

Punch cards were for the CS weenies. ;-) The real nerds had slip-stick scabbards hanging from their belts (I carried mine with my books). Over my senior year, the slip-sticks were being replaced by calculators (and holsters for scabbards ;-). I bought an HP, and yes, it was $400 (about 10-weeks gross pay).
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On 12/19/2013 11:13 AM, snipped-for-privacy@attt.bizz wrote:

had it. ^_^
TDD
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On Thu, 19 Dec 2013 11:45:23 -0600, The Daring Dufas wrote:

My Dad, bless his heart, taught me how to use a slide rule when I was in high school trig class. His was bamboo and white, as I remember it. He bought me a smaller one, and I cherished it. I hope I still have it, but, I've moved a half dozen times since so it's somewhere.
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Danny D. wrote:

I still have mine in a leather case on my study desk shelf.
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