Senao NL-3054CB3 PtP Bridge help

mlee2 · 05-31-2004

Hi,
I need some help/advice.
I live in a very rural community. I have set up 2 Senao NL-3054CB3 "long-range" access points to connect my home to my office to share Internet connection. I picked these particular units, since I understand they are 200mw units. My office is aprpx. 3500 ft from my home. I have a 24Dbi parabolic directional antenna at each location. There are a few tree lines in between, but hoping the stronger output and higher gain antennas would burn a path between my 2 locations. My antennas are mounted aprox 40 ft above ground on antenna mast. I am using 50 ft LMR-400 cable and approprate pigtails at each location.
I have set the units up in point-to-point bridge mode. I have reduced my transmission rate down to 1 Mbits/s and set the connection mode down to 802.11b only to make a connection. Anything higher appears to not be able to make a connection. I have also tried different various channels. I consistantly have between 62% to 65% communications strength. But even with this signal strength, I cannot make a link most of the time.
When I do make a link, the remote computers are assigned IP addresses, and the Internet connection is functional. I have ran Qcheck. My throughput will run anywhere from 20 Kbps to 700 Kbps, if the test doesn't time out.
Shouldn't 62-65% signal be enough to make a decent (or at least reliable) connection? Any pointers/ideas would be greatly appreciated!!

itsnotme · 06-01-2004

Put on your flame-retardant underwear, cross-posting is a no no here. May I suggest you delete your other post before the locusts descend on you.

Thorn · 06-01-2004

Short answer: No, I wouldn't expect it to work.

Options:
Get higher masts. At 3500 ft., you need to have the antennae about 20' above the trees. Twenty-five feet would be better, and allow for some future growth.

Get a chain saw, and clear the path between the existing masts; 20' to 25' wide.

Move to another frequency which penetrates trees better. (e.g. 900MHz)

mlee2 · 06-01-2004

...so a solid 62-65% signal strength isn't strong enough??
Thx

Thorn · 06-01-2004

Quote:

Originally Posted by mlee2

...so a solid 62-65% signal strength isn't strong enough??
Thx

62-65% of what? To accurately evaluate it, you need a real measurement like deciBels (dB).

I understand that's what the machine is saying, but it's a useless figure, since there's nothing to reference to it. Not your fault, but manufacturers dumb down the interfaces because people get scared when they see things they don't understand, like "deciBels". Unfortunately, they dumb it down so much as to be useless.

In any event, based on what you've described, there is no way I'd expect to get any usable signal and bandwidth.

mlee2 · 06-01-2004

thanks for the reply.
Getting 20-30 ft above the trees would not be possible. But since I have a signal that works sometimes, would you think that another 20 ft height would be good enough to have a workable signal? I realize I will never get 54, or even 11 mbps. I only need 1Mbps to share Internet...
Thanks

Thorn · 06-01-2004

Maybe. But only if you're nickname is "Lucky" and you sacrifice a goat to the radio gods.

Getting higher may not help unless you get the Fresnel Zone cleared. You're fighting physics here.

The problem is you need to clear what is known as the Fresnel Zone. (Google on "Fresnel Zone.") It is a circular area, that has to have 60% minimum of the zone clear of any obstructions in order for the signal to get through reliably. For 2.4Ghz the FZ at 3/4 mile (3960') is about 20' in diameter. You can block 20% of that distance and be OK; 30%-40% gets touchy; over 40% and it usually won't work.

mlee2 · 06-01-2004

Thorn, Thanks again for the reply.
One other thought I just had... I am looking out my office window at out local water tower about 200 yards away. It is maybe 150 ft tall. Would it be possible to bounce a signal off of the water tower if both antennas were pointing it?
Any thoughts would be appreciated.

G8tK33per · 06-01-2004

Quote:

Originally Posted by mlee2

Thorn, Thanks again for the reply.
One other thought I just had... I am looking out my office window at out local water tower about 200 yards away. It is maybe 150 ft tall. Would it be possible to bounce a signal off of the water tower if both antennas were pointing it?
Any thoughts would be appreciated.

water tower bounce??

Thorn · 06-01-2004

The info in the thread G8tk33per listed is still what I'd say.

Thanks, G8t.

hydro27405 · 06-01-2004

I've had good luck fighting trees with WifiPlus antenna's. A little spendy but they do work. I use 1 of the 4 inch beams on my tower and managed to shoot through a 100 feet of tree's a mile and a half away from the tower.
I'm using a 200mw radio on tower and a Smartbridges Air Bridge Outdoor with the 18 inch beam on customer house. I show 90% link quality and 80-85% RSSI.
Hydro

OOPS forgot the web site
www.wifi-plus.com

05-31-2004	#1 (permalink)
mlee2 Registered Member Join Date: May 2004 Posts: 6	Senao NL-3054CB3 PtP Bridge help Hi, I need some help/advice. I live in a very rural community. I have set up 2 Senao NL-3054CB3 "long-range" access points to connect my home to my office to share Internet connection. I picked these particular units, since I understand they are 200mw units. My office is aprpx. 3500 ft from my home. I have a 24Dbi parabolic directional antenna at each location. There are a few tree lines in between, but hoping the stronger output and higher gain antennas would burn a path between my 2 locations. My antennas are mounted aprox 40 ft above ground on antenna mast. I am using 50 ft LMR-400 cable and approprate pigtails at each location. I have set the units up in point-to-point bridge mode. I have reduced my transmission rate down to 1 Mbits/s and set the connection mode down to 802.11b only to make a connection. Anything higher appears to not be able to make a connection. I have also tried different various channels. I consistantly have between 62% to 65% communications strength. But even with this signal strength, I cannot make a link most of the time. When I do make a link, the remote computers are assigned IP addresses, and the Internet connection is functional. I have ran Qcheck. My throughput will run anywhere from 20 Kbps to 700 Kbps, if the test doesn't time out. Shouldn't 62-65% signal be enough to make a decent (or at least reliable) connection? Any pointers/ideas would be greatly appreciated!!

06-01-2004	#3 (permalink)
Thorn Did you do the math? Join Date: Apr 2002 Location: Villa Straylight Posts: 10,351	Short answer: No, I wouldn't expect it to work. Options: Get higher masts. At 3500 ft., you need to have the antennae about 20' above the trees. Twenty-five feet would be better, and allow for some future growth. Get a chain saw, and clear the path between the existing masts; 20' to 25' wide. Move to another frequency which penetrates trees better. (e.g. 900MHz) __________________ Thorn "Read Altas Shrugged. Compare it to today. Repeat as necessary"

06-01-2004	#7 (permalink)
Thorn Did you do the math? Join Date: Apr 2002 Location: Villa Straylight Posts: 10,351	Maybe. But only if you're nickname is "Lucky" and you sacrifice a goat to the radio gods. Getting higher may not help unless you get the Fresnel Zone cleared. You're fighting physics here. The problem is you need to clear what is known as the Fresnel Zone. (Google on "Fresnel Zone.") It is a circular area, that has to have 60% minimum of the zone clear of any obstructions in order for the signal to get through reliably. For 2.4Ghz the FZ at 3/4 mile (3960') is about 20' in diameter. You can block 20% of that distance and be OK; 30%-40% gets touchy; over 40% and it usually won't work. __________________ Thorn "Read Altas Shrugged. Compare it to today. Repeat as necessary"

06-01-2004	#10 (permalink)
Thorn Did you do the math? Join Date: Apr 2002 Location: Villa Straylight Posts: 10,351	The info in the thread G8tk33per listed is still what I'd say. Thanks, G8t. __________________ Thorn "Read Altas Shrugged. Compare it to today. Repeat as necessary"

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06-01-2004	#2 (permalink)
itsnotme Dumbass checker Join Date: Sep 2002 Location: Somewhere below Lake Ontario Posts: 1,076	Put on your flame-retardant underwear, cross-posting is a no no here. May I suggest you delete your other post before the locusts descend on you.

06-01-2004	#4 (permalink)
mlee2 Registered Member Join Date: May 2004 Posts: 6	...so a solid 62-65% signal strength isn't strong enough?? Thx

06-01-2004	#6 (permalink)
mlee2 Registered Member Join Date: May 2004 Posts: 6	thanks for the reply. Getting 20-30 ft above the trees would not be possible. But since I have a signal that works sometimes, would you think that another 20 ft height would be good enough to have a workable signal? I realize I will never get 54, or even 11 mbps. I only need 1Mbps to share Internet... Thanks

06-01-2004	#8 (permalink)
mlee2 Registered Member Join Date: May 2004 Posts: 6	Thorn, Thanks again for the reply. One other thought I just had... I am looking out my office window at out local water tower about 200 yards away. It is maybe 150 ft tall. Would it be possible to bounce a signal off of the water tower if both antennas were pointing it? Any thoughts would be appreciated.

06-01-2004	#11 (permalink)
hydro27405 Registered Member Join Date: Dec 2002 Location: MN Posts: 96	I've had good luck fighting trees with WifiPlus antenna's. A little spendy but they do work. I use 1 of the 4 inch beams on my tower and managed to shoot through a 100 feet of tree's a mile and a half away from the tower. I'm using a 200mw radio on tower and a Smartbridges Air Bridge Outdoor with the 18 inch beam on customer house. I show 90% link quality and 80-85% RSSI. Hydro OOPS forgot the web site www.wifi-plus.com