lutful
Premium
join:2005-06-16
Ottawa, ON
 ·TekSavvy Solutions..
| Current longest 5.8Ghz OFDM link?
I know 2.4Ghz PtP has broken the 100km barrier, but what is the world record for 5.8Ghz? I have heard of 40km but not 60km.
I was thinking that the world's smallest SR5 radios directly attached to the feeds of 6ft dishes emitting 200W EIRP may kill two birds (  ) in one test ?
All suggestions on good test sites and antenna alignment strategies welcome. |
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ponline
join:2004-03-04
presheva | What kind of board is that? |
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Semaphore
Premium
join:2003-11-18
Arnprior On. | looks like an ubiquiti SR5 to me |
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cmaenginsb
Premium,MVM
join:2001-03-19
Palmdale, CA
| reply to lutful
There is a 118km Redline link in the US. It's only running at the lowest modulation with 2 foot dishes on each side.
I've done a couple 48 kilometer links with Redlines at 64 QAM with a 3' dish on one side and a 4' on the other one.
I also did a 77 kilometer link with 10' dishes on each side, also running Redlines with 64 QAM. (I cheated on that one, the dishes were installed and pre-aligned)
As to alignment we generally would get accurate GPS coordinates and use a mapping application to get a bearing for initial azimuth. Elevation was a guestimate.
Personally while it's cool to talk about long links, most of them are not engineered in such a way as they will be stable over the long run. In the case of the links I put up we had a minimum of 20 db fade margin.
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CCNA, Comtrain Certified Tower Climber |
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lutful
Premium
join:2005-06-16
Ottawa, ON
·TekSavvy Solutions..
| reply to Semaphore
said by Semaphore  :looks like an ubiquiti SR5 to me Yes, but the SR5 miniPCI card is isntalled on a tiny 3x3 inch 333Mhz -40C to +85C rated PowerPC motherboard with 64MB RAM and 16MB flash.  |
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ponline
join:2004-03-04
presheva
| said by lutful :said by Semaphore :looks like an ubiquiti SR5 to me Yes, but the SR5 miniPCI card is isntalled on a tiny 3x3 inch 333Mhz -40C to +85C rated PowerPC motherboard with 64MB RAM and 16MB flash. Yes, i was asking about the board not the sr5 miniPci.
Very good performance board for such tiny dimensions, can you provide some links with more info and where to get them?
thanks |
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milbrath
join:2006-03-27
Dresden, TN
| I don't like the sound of that superdog. I have 6 TR5a-24f models I'm going to use for some PTP's to 3 water towers in the area(hope to atleast, one of them is 8 miles) I try to run everything in routed mode (with the exception of PTP's) so the ARP issue should not give me problems. Anyone got any other issues the the tr5a's in PTP.
Milbrath |
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superdog
I Need A Drink
Premium,MVM
join:2001-07-13
Lebanon, PA
| said by milbrath :I don't like the sound of that superdog. Milbrath You will be fine. I have 2 other sets running, and they have no issues, and they have been up for over 15 months without a reboot or any other issues. I am curious as to why You posted an answer to a post I made in this thread: »Tranzeo 5a Turbo mode bench results
In this one??, Not that I care?, I just found it odd?. Kinda' funny actually!
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»www.wavecrazy.net Join WISPA today! »www.wispa.org/ |
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milbrath
join:2006-03-27
Dresden, TN | I did didn't I! I hate mornings, hijacked this thread enough. Back to the main topic we do have a redline unit doing 25 miles. Been rock solid for a year. 2 foot panels on each end, relatively poor los. Alignment took awhile.
Milbrath |
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cmaenginsb
Premium,MVM
join:2001-03-19
Palmdale, CA
| reply to lutful
I don't know if it's luck, but most of the long range links I've done (15 miles or more) have been within 3-4 Db of calculations when we first turn the radios on. We can usually tweak to get another 2-3 Db better.
I do remember a 25 mile link (started as a Wilan AWE120-58 and is now a Redline) that I couldn't get better than 5 db above the recieve threshold.
At the time I though it was because I was shooting through a tower at one end. Finally my friend went down to the end I had been working on and I got a big suprise. When I first connected I got the sidelobe of the 4' dish I was using, so moving the dish either direction would reduce signal strength. Had I kept going in the right direction, eventually I would have found a much higher RSSI (that link was better than calcs).
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CCNA, Comtrain Certified Tower Climber |
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lutful
Premium
join:2005-06-16
Ottawa, ON
·TekSavvy Solutions..
| said by cmaenginsb :I don't know if it's luck, but most of the long range links I've done (15 miles or more) have been within 3-4 Db of calculations when we first turn the radios on. We can usually tweak to get another 2-3 Db better. It is not luck - you are a very experienced installer with RF knowledge, so your links come out close to calculated RSSI. The very best I ever heard of was within 2dB of caculation on a short 250m link.
I am looking at a modified challenge where link distance and antennas are fixed, but people try to create very stable links with the best throughput over a few days.
So, the best 25km link or the best 100km link will win rather than a temporary 120km link at 1Mb/s and 50% packet error. |
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