What does Polarisation: Linear, Beamwidth: (Azimuth / Elevation) 5° / 6° mean

[Kameelperdza]

I have the option to buy http://www.scoopdistribution.co.za/product_info.php?cPath=49_37&products_id=855 or the http://www.scoopdistribution.co.za/product_info.php?cPath=49_37&products_id=277

But i cant make my mind up and i dont know what some of the features in the http://www.scoopdistribution.co.za/product_info.php?cPath=49_37&products_id=855 model means.

What is so cool about that one(the R495 one)

At the moment im using 24dbi 5ghz grid to connect two highsites to each other.Which one will give me most value and best service.

If anyone can help me then that would be great. thanx

 

[marine1]

Stay away from the 30/31, go for the 27.

 

[Kameelperdza]

Stay away from the 30/31, go for the 27.

What is the reason why i should not go 30/31?

 

[marine1]

I went from 27 to 31 and it made it worse, much harder to align and lock on to a signal.

 

[Kameelperdza]

Oh thankyou for that, i think i will go with 27dbi then.

Thank you

 

[marine1]

I would really not recommend the bigger one.
One would think that bigger is better but not so in this instance.

 

[Kameelperdza]

At the moment im getting signal strengh of -82 and packet throughput of 14200kbps

I have done test and get 1.6mb/s when transfering files.

The distance is 1.2km between sites. There is some trees in the way. I tried 2.4ghz but 2 much interference.

I wonder if 27dbi will improve performace?

Usunaly when the wind blows then i get reassociating and severe packet loss
Im using 24dbi at the moment and is on channel 3200

 

[portcullis]

Stay away from the 30/31, go for the 27.

I agree with you on this.

I have a link from a high site to a point 6.3km away using 2 x 30/31's. The signal strength is -77.
I have another link from the same site high site to a point 8.8km away using 2 x 24's. The signal strength is -75.

Those aerials are not only big, but they're really not great. I've seen a number of guys removing these big things from their towers lately and replacing them with dishes.

I'm going to go the other route, remove them and replace with with 24dBi's.

 

[Kameelperdza]

I agree with you on this.

I have a link from a high site to a point 6.3km away using 2 x 30/31's. The signal strength is -77.
I have another link from the same site high site to a point 8.8km away using 2 x 24's. The signal strength is -75.

Those aerials are not only big, but they're really not great. I've seen a number of guys removing these big things from their towers lately and replacing them with dishes.

I'm going to go the other route, remove them and replace with with 24dBi's.

I have 24dbi grids at the moment. Everyone says i should have gotten 2.7dbi. Now im wondering if i should replave the 24dbi with 27dbi.

 

[portcullis]

What's the problem with the link?

Maybe we can give you some advice.

 

[marine1]

27 would be the best IMO.
I had a 27 and it was great - changed it for the 31 as I thought it would be better - I was wrong

 

[Pilgrim]

I have 24dbi grids at the moment. Everyone says i should have gotten 2.7dbi. Now im wondering if i should replave the 24dbi with 27dbi.

What is the distance? We run a 16km backbone link on 24dbi grids, and they work like a charm. 27 is a bit better yes, but 30/31 is overkill. Only use it if you really, really need it. Eg. a 40km link.

 

[Kameelperdza]

1.2.km. ìs the distance between my 2 sites. .i wonder if i put 27dbi if my signal strengh wil improve.at the moment i get -82

 

[daffy]

1.2km? a 21dB will be more than enough.
If you're still struggling, You have other problems.
Alignment?
Make sure your antennas on both ends are polarised correctly...
Whats the antenna on the other end?

 

[portcullis]

1.2km

You should be able to get away with these two.
http://www.scoopdistribution.co.za/product_info.php?cPath=49_38&products_id=598

What radios are you using each side? How long are the aerial cables? Is the cable LMR400 or the thin stuff? Are the cable connectors terminated properly? Have the connections been waterproofed?

Are there trees of buildings blocking the line of site?
Have you worked out what the fresnel zone is?

The first thing that you need to do is to see what's going on in the air around where the radios are.

Assuming you are running MikroTik, go to Wireless - Interfaces - select the radio and then click on Snooper and start the snooper.

Do this on each side, physically at each location. Don't run the snooper remotely on the interface you are connecting to, or your link will die.

Sometimes switching roles and making the station the AP and the AP the station changes the quality of a connection for the better. I've been in RF comms for many years and I still don't understand why, though.

You need to find a frequency that's clear on both sides. You then need to look at the aerial spec sheets to see what frequencies they've been cut for. You can't use a 5475 - 5575MHz antenna on 5800MHz or 5200MHz and expect it to work.

You then need to align the aerials properly. Are you running the link vertically or horizontally? It's much more difficult aligning a horizontal link.

 

[Kameelperdza]

they are both 24dbi grids. i tried to align them and -79 is the best that i get..maybe if i try to put my antenas higher and above the trees.

 

[portcullis]

they are both 24dbi grids. i tried to align them and -79 is the best that i get..maybe if i try to put my antenas higher and above the trees.

Trees?

Do you have clear line of site between the two points?

 

[daffy]

they are both 24dbi grids. i tried to align them and -79 is the best that i get..maybe if i try to put my antenas higher and above the trees.

Dejavu... I'm pretty sure the Jawug guys have told you many many times that trees are a bad thing.

 

[portcullis]

It doesn't matter how powerful the radio is or how big the aerials are, you simply cannot blast through trees.

IN RF terms, a tree is equavalent to a sheet of lead.

 

[Kameelperdza]

yes sum stupid trees.wish i could get rid of them. sumtimes my signal is -75 and sumtimes -92. i dont have clear sight of other end but to look on google earth for the best position