Water Tower Antenna Selection

nhlcreation · 04-03-2008

I work at a school that gets their internet from a wireless provider. The isp's antennas are on the water tower no more than 100 yards away. Right now the school has an omni antenna just attached to the roof. We have problems with drop outs and slow speeds daily. My question is, given the radiation pattern of an omni antenna and the schools relatively short distance from the water tower, do you think I could replace the school's omni antenna with something like a panel antenna pointed at the water tower and that would help? Any help would be greatly appreciated.

streaker69 · 04-03-2008

Quote:

Originally Posted by nhlcreation

I work at a school that gets their internet from a wireless provider. The isp's antennas are on the water tower no more than 100 yards away. Right now the school has an omni antenna just attached to the roof. We have problems with drop outs and slow speeds daily. My question is, given the radiation pattern of an omni antenna and the schools relatively short distance from the water tower, do you think I could replace the school's omni antenna with something like a panel antenna pointed at the water tower and that would help? Any help would be greatly appreciated.

Yep, that would be a good idea.

Make sure the ISP is ok with you doing that before you do it though, they'll probably be able to provide you with some assistance in selecting the correct kind of antenna.

Starpoint · 04-03-2008

Quote:

Originally Posted by nhlcreation

I work at a school that gets their internet from a wireless provider. The isp's antennas are on the water tower no more than 100 yards away. Right now the school has an omni antenna just attached to the roof. We have problems with drop outs and slow speeds daily. My question is, given the radiation pattern of an omni antenna and the schools relatively short distance from the water tower, do you think I could replace the school's omni antenna with something like a panel antenna pointed at the water tower and that would help? Any help would be greatly appreciated.

Best idea would be 2 directionals..... if you can get some really fine beam ones and aim them at each other. this way you get the best reception.

brwrdrvr · 04-03-2008

Quote:

Originally Posted by nhlcreation

I work at a school that gets their internet from a wireless provider. The isp's antennas are on the water tower no more than 100 yards away. Right now the school has an omni antenna just attached to the roof. We have problems with drop outs and slow speeds daily. My question is, given the radiation pattern of an omni antenna and the schools relatively short distance from the water tower, do you think I could replace the school's omni antenna with something like a panel antenna pointed at the water tower and that would help? Any help would be greatly appreciated.

I would find out if your wISP is having the drop outs and slow downs or if it is your network having the problem before changing out anything. If you set up a directional antenna on your end that would definitely get you a better link to the wISP, but might not solve the problem.

streaker69 · 04-03-2008

Quote:

Originally Posted by brwrdrvr

I would find out if your wISP is having the drop outs and slow downs or if it is your network having the problem before changing out anything. If you set up a directional antenna on your end that would definitely get you a better link to the wISP, but might not solve the problem.

I can imagine how that phone call is going to go. Isn't that pretty much the nice way of asking if their service sucks the smelly end of a donkey?

brwrdrvr · 04-03-2008

Quote:

Originally Posted by streaker69

I can imagine how that phone call is going to go. Isn't that pretty much the nice way of asking if their service sucks the smelly end of a donkey?

Yes. Probably. I just gave my best shot at giving some "constructive" advice instead of my usual "destructive" advice.

little dave is on a wISP and I think he said his ISP's antenna is a good distance away. He has some slow down when the traffic is heavy, but other than that it's good. I just figured if they came and looked at their antenna and gave it the "ok" then the OP can at least look into what the real problem is instead of throwing school money out the window.

Thinking back on my RF days, if the wISP is pushing a good amount of power and the receiver in the school isn't properly shielded than they could be getting some interference from the "front-end".

If I had any experience with wISP's I guess I could be more help. How much "power" does a wISP push anyways? I would figure that the ISP's antenna would be at an excellent position being only 100 yards away.

streaker69 · 04-03-2008

Quote:

Originally Posted by brwrdrvr

Yes. Probably. I just gave my best shot at giving some "constructive" advice instead of my usual "destructive" advice.

We're not used to that from you, now stop it.

Quote:

If I had any experience with wISP's I guess I could be more help. How much "power" does a wISP push anyways? I would figure that the ISP's antenna would be at an excellent position being only 100 yards away.

Except the OP neglected to mention the forest of 300ft tall aluminum christmas trees that span those 100yrds.

MikeP928 · 04-03-2008

BTDT.

Even with a directional on top of the school, you are probably under the radiation pattern of the omni. I went through this with a school that had an omni on a 150' tower across the street. Putting a directional on top of the school helped slightly, but the signal was so poor it did not help much.

If the omni is on the side of the tank, there is no point in having an omni, the tank is blocking half the signal pattern anyway. If it is on top, the tank is blocking you.

You can check on the signal with a spectrum analyzer (best idea for several reasons) or use NS with the SUPPORTED card and a directional to see if you have enough signal to work with.

Check the signal and use your results to push the ISP to install a directional aimed downward at the school.

MikeP

Thorn · 04-03-2008

Quote:

Originally Posted by MikeP928

Even with a directional on top of the school, you are probably under the radiation pattern of the omni.

Yeah, that would my guess, too. Although it's just a guess based on the description.

brwrdrvr · 04-03-2008

I know it's possible, but would'nt have thought about being under the antenna's radiation unless I was there looking at the set up.

Maybe that why I sit all comfy and cozy in my office on my own little network. I always visualize the set up being perfect.<sarcasm> Only because if a "Professional" ISP set it up, it should be perfect, right? <end sarcasm>
I miss my old CB days when we start talking about this stuff.

Quote:

Originally Posted by streaker69

We're not used to that from you, now stop it.

It did feel a little unatural.

MikeP928 · 04-03-2008

Quote:

Originally Posted by brwrdrvr

I know it's possible, but would'nt have thought about being under the antenna's radiation unless I was there looking at the set up.

Maybe that why I sit all comfy and cozy in my office on my own little network. I always visualize the set up being perfect.<sarcasm> Only because if a "Professional" ISP set it up, it should be perfect, right? <end sarcasm>
I miss my old CB days when we start talking about this stuff.

It did feel a little unatural.

I had one school where the ISP would not let the tech replace the omni, but sent him out to adjust it. Once he understood the problem (picture standing under a 150' tower explaining antenna theory to a guy that installs them for a living, duh), I got him to rotate it horizontal and aim it perpendicular to the line to the school. We rotated a yagi to horizontal polarity and aimed it up to the tower. Worked great, tasted just like chicken.

Yeah, they forgot to teach you that one in wireless classes.

MikeP

Airstreamer · 04-03-2008

We had a similar problem with a 15 dbi omni. The tower was tall enough that you had the 'fender washer' pattern up high. Replacing it with a 9 dbi that also has an additional electrical downtilt of 7 degrees made life much better.

little dave · 04-04-2008

Quote:

little dave is on a wISP and I think he said his ISP's antenna is a good distance away

7 miles
I don't know whats on the ISP's antenna but I have a 24 dbi grid antenna on my tv tower.Beats the hell out of dial up. Only time I've lost service was when they got hit by lightning.

brwrdrvr · 04-04-2008

I was wondering if the OP was going to come back and thank us for our great advice until I seen that he/she registered one April 2006 and just made his/her first post in this thread. I guess we will have to wait another year for the OP's next post.

nhlcreation · 04-04-2008

Thanks to all those who posted replies. I'm going to contact the isp and see what they recommend. Just hoping it's not going to be a pain in the a$$ to fix.

04-03-2008	#1 (permalink)
nhlcreation Registered Member Join Date: Apr 2006 Posts: 2	Water Tower Antenna Selection I work at a school that gets their internet from a wireless provider. The isp's antennas are on the water tower no more than 100 yards away. Right now the school has an omni antenna just attached to the roof. We have problems with drop outs and slow speeds daily. My question is, given the radiation pattern of an omni antenna and the schools relatively short distance from the water tower, do you think I could replace the school's omni antenna with something like a panel antenna pointed at the water tower and that would help? Any help would be greatly appreciated.

04-03-2008	#8 (permalink)
MikeP928 Heeere's your sign! Join Date: May 2002 Location: Mexico Beach, FL Posts: 1,164	BTDT. Even with a directional on top of the school, you are probably under the radiation pattern of the omni. I went through this with a school that had an omni on a 150' tower across the street. Putting a directional on top of the school helped slightly, but the signal was so poor it did not help much. If the omni is on the side of the tank, there is no point in having an omni, the tank is blocking half the signal pattern anyway. If it is on top, the tank is blocking you. You can check on the signal with a spectrum analyzer (best idea for several reasons) or use NS with the SUPPORTED card and a directional to see if you have enough signal to work with. Check the signal and use your results to push the ISP to install a directional aimed downward at the school. MikeP __________________ Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote. -- Benjamin Franklin, 1759

04-03-2008	#12 (permalink)
Airstreamer Sniffin' the aether Join Date: Nov 2004 Location: A little North of Reason Posts: 2,726	We had a similar problem with a 15 dbi omni. The tower was tall enough that you had the 'fender washer' pattern up high. Replacing it with a 9 dbi that also has an additional electrical downtilt of 7 degrees made life much better. __________________ "Wait just a minute, now. Whaddya mean, you DON'T use Regedit to send email?" Last edited by Airstreamer : 04-03-2008 at 09:53 PM.

04-04-2008	#14 (permalink)
brwrdrvr Cajun from Hell Join Date: Feb 2005 Location: Capitol City, Louisiana Posts: 3,137	I was wondering if the OP was going to come back and thank us for our great advice until I seen that he/she registered one April 2006 and just made his/her first post in this thread. I guess we will have to wait another year for the OP's next post. __________________ No I do not. I live in my own basement.

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04-04-2008	#15 (permalink)
nhlcreation Registered Member Join Date: Apr 2006 Posts: 2	Thanks to all those who posted replies. I'm going to contact the isp and see what they recommend. Just hoping it's not going to be a pain in the a$$ to fix.