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Author Topic: 802.11 Use?  (Read 7033 times)
K4RAF
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Posts: 19


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« on: January 22, 2006, 10:38:57 AM »

After looking at references to 802.11 in these forums, it seems there is a lacking amount of participation.

I am curious if anyone is currently using or experimenting with 802.11?

I am currently experimenting with several connections, up to 25 miles. I would love to hear form anyone, but especially those in the VA/NC area.

If you do not want to express your use publicly, you can write me at k4raf@yahoo.com

PS: I am not looking for legal opinions, just actual usage!
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N5PVL
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Posts: 209




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« Reply #1 on: January 23, 2006, 05:46:35 PM »


I've been looking for actual use too, for several years now... There's lots of talk, but not much 'do'.

AX25 will get you past the legal questions, but you'll have to seperate yourself from the tcpip tit to do that.

Charles,  N5PVL
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K4RAF
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« Reply #2 on: January 25, 2006, 10:22:01 PM »

Hmmm, 1200 baud vs 11 or 54mbps...

Why even bother?
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N5PVL
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Posts: 209




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« Reply #3 on: January 28, 2006, 04:59:12 AM »


Hmmmm... Thinking AX25 is associated with a single baud rate, when it is quite usable with 802.11 equipment, and has been utilized with high baud rates in Europe for decades...

Why bother "thinking" at all?

Charles,  N5PVL
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N9LYA
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Posts: 17


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« Reply #4 on: April 25, 2006, 08:11:40 AM »

Hi Charles,

That very lack of thinking you keep running into here at Eham.. And elsewhere.. Is what has held back Amateur Radio for years.. Those who know, and those who think they know.. And those who do not think..

Gee who would ever think AX25 was held at a single baud rate... Doh...

Keep up the good work my friend.. Someday you will find someone else, who thinks... And not stinks.

Wink
73 Jerry N9LYA
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N1KK
Member

Posts: 20




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« Reply #5 on: March 01, 2013, 08:02:29 AM »

Has anyone figured out how to use a couple laptops with WiFi adapters and send video and audio
direct, no internet or Routers involved?

Ken
N1KK
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KU7PDX
Member

Posts: 50


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« Reply #6 on: March 01, 2013, 08:30:22 AM »

Has anyone figured out how to use a couple laptops with WiFi adapters and send video and audio
direct, no internet or Routers involved?

Ken
N1KK
Hi Ken,

What you want to do is set up the wifi adapters in Ad-hoc mode. This will allow them to talk to each other without going through an access point/router.
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73,
Chris - KU7PDX
K0JEG
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Posts: 622




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« Reply #7 on: March 02, 2013, 08:03:35 AM »

I've seen some articles from a group in Texas running a wide area network on modified 802.11 gear. Google can't seem to find the link now.

Our club president asked me to look into setting up an 802.11(x) link between our tower site and a club member's home (and on to the Internet). First thing I asked was "what for?" The answer was "whatever." Needless to say, it's a low priority.

I think it came up because another member asked about putting a web camera on the tower and suggested using a Verizon 4G card to transmit. I overheard the conversation and reminded the member that we already had more spectrum than Verizon, available for the hardware cost, much of which sits idle.

While I would love to see high speed networks interconnecting our repeater sites sans wired infrastructure, the truth is setting up this stuff isn't easy or cheap if you want reliable. It also gets difficult because most of the long-haul (>40 miles) equipment and protocols aren't designed for ham radio and our requirements for ID and other issues. A cell phone tower can transmit a constant QAM or other carrier for timing and other purposes, which isn't permitted under our rules. This makes syncing radios difficult and greatly increases turn-around time on transceivers. Until there's a real "killer app" for high data rate networks, I think we're stuck with going the other direction (low speed, very low bandwidth, low SNR) communications.

As for the legalities of running 802.11 protocols on 2.4GHz, we're the primary user of the band, so everyone else (theoretically) has to accept any interference we produce. As long as you don't encrypt and use your callsign in the SSID you're good to go.
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W8JX
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Posts: 5321




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« Reply #8 on: March 02, 2013, 11:59:57 AM »

The "problem" with 802.11 is not just the power level but also the protocol timing does not support long range connections as well. (beyond 2 miles or so).  You need to use 802.16e (WiMax) as it was designed for this.   
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Entered using a  WiFi Win 8.1 RT tablet or a Android tablet using 4G/LTE or WiFi.
WA6MJE
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Posts: 71




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« Reply #9 on: March 03, 2013, 05:41:27 PM »

I have been working on an amateur television link from an RC airplane to the ground. They call this FPV or First Person View flying.  The experience is like being seated in the RC airplane. 

There is a great deal of equipment on 900 Mhz up to 5.8 Ghz to transmit and receive video.  However, this is at this point not HD video. 

In considering alternatives, I have looked over WiFi solutions that are capable of carrying the bandwidth of HD television.  But, from what I hear, there is a delay due to the codecs used that render the video useless for flying the airplane, ie. you will not react in time. 

But, I still have experimenting with this in mind.  I am building an RC drone for this spring, and want a video data link back down, and am looking at options including 802.11b, g, and so on. I have to consider weight of the transmitter, and power consumption as well as delay.  It will be a fun project.

Rene - WA6MJE
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KE7EYX
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Posts: 41




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« Reply #10 on: March 03, 2013, 06:02:37 PM »

Believe this is what K4RAF and K0JEG were talking along the lines of and about. Here is a real easy way to make a site to site network for several uses internet, ip webcam to remote locations like a clubs repeater tower with out the high costs of some sort of DSL/Cable/Satellite service to get it. Anything that can communicate over a standard TCP/IP network will work over HSMM-MESH  Requires line of site between the two points.  
http://www.hsmm-mesh.org/

Map of how it works.
http://www.hsmm-mesh.org/visual-of-a-mesh-network.html

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W8JX
Member

Posts: 5321




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« Reply #11 on: March 03, 2013, 07:27:37 PM »

But, I still have experimenting with this in mind.  I am building an RC drone for this spring, and want a video data link back down, and am looking at options including 802.11b, g, and so on. I have to consider weight of the transmitter, and power consumption as well as delay.  It will be a fun project.

No matter how much you boost power or ERP via antennas you will reach a point around 2 miles or so where the 802.11 protocol is no longer viable. It has to do with handshaking timings which can increase with distance as it is a short range protocol. 802.16 WiMax protocol timing was designed for longer distances.
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Entered using a  WiFi Win 8.1 RT tablet or a Android tablet using 4G/LTE or WiFi.
N1ZZZ
Member

Posts: 160




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« Reply #12 on: March 05, 2013, 06:31:16 AM »

This kind of work isn't all that new or unusual, at least in the commercial world.  Wireless ISP's use this kind of gear to get broadband signals via RF all over the place.  They tend to use unlicensed segments in the 900 MHZ as well as 2.4 and 5 GHZ bands.

I am actually surprised that more repeaters using Echolink/IRLP/D-Star don't use this equipment to connect remote sites to the internet.

In any case, here is a website that repairs and sells the hardware to do this sort of thing:

http://www.wirelessunits.com/

73
Jeremy N1ZZZ
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WW3JR
Member

Posts: 4




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« Reply #13 on: June 27, 2013, 09:49:10 AM »

The group in Texas does have a working web site http://hsmm-mesh.org/ and their application works well.  I've put together a small mesh talking to my Raspberry Pi's.  Be cautious of the version of the Linksys router used however.  See the web site for information on applicable versions.

73,

John WW3JR
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K0JEG
Member

Posts: 622




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« Reply #14 on: June 28, 2013, 01:23:11 PM »

But, I still have experimenting with this in mind.  I am building an RC drone for this spring, and want a video data link back down, and am looking at options including 802.11b, g, and so on. I have to consider weight of the transmitter, and power consumption as well as delay.  It will be a fun project.

No matter how much you boost power or ERP via antennas you will reach a point around 2 miles or so where the 802.11 protocol is no longer viable. It has to do with handshaking timings which can increase with distance as it is a short range protocol. 802.16 WiMax protocol timing was designed for longer distances.

That's mostly true. However this field day we picked up an outdoor access point that has a way to adjust timing to get distances out to 45KM:

http://www.engeniustech.com/business-networking/outdoor-access-points-client-bridges/16125-enh200ext

We didn't test this, I just wanted something that we could put on a mast that was weatherproof and provide good coverage over a 200' radius. I don't know if it is still technically 802.11 protocol, but the idea is sound and should work. Also, if you would want to attempt to set distance records you will need line of site, very directional antennas and more than the normal 18dBm power output. DD-WRT will also let you adjust timing to allow for greater distance.

The unit above will output 30dBm and was attached to a 6dB gain antenna and provided very good coverage of the field day site (until someone decided to shut down the generator, then got upset because the UPS alarm was keeping him awake!). Since all it was doing was providing N1MM a network path I don't know how the latency was, but I imagine it was just fine.
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