Antenna testing

shooter64738 · EVDO User Joined: 07 Sep 2007 Posts: 41

I've been comparing some different antennas, and here is what I have so far, from worst to best. In the comparison I placed all the antennas in the same location, and for the omni antenna I clamped it to a 3'x3' piece of sheet metal for a grounding plane.

Here it is:
Pros-Obviously with the internal antenna you are more mobile.
Cons-If you get in a fringe area, you may loose connection

Pros-Better reception than no external in fringe area. No pointing, good for attaching to a vehicle.
Cons-Those fringe areas again. Take the good with the bad.

Pros-Not to bad of an antenna, but I was really hoping it would pull in a better signal. Good for fringe areas if your locking to one tower. Aiming isn't too hard. Beam width is pretty wide.
Cons-I hoped for more gain. No mobility, little pricey for me. (glad it belongs to the neighbor)

Pros-Great reception with it. Good for locking to one tower. Terrific gain. Dirt cheap.
Cons-They can be bulky depending on the dish. As with the yagi, no mobility. Takes some know how to put one together. Aiming is more difficult, narrow beam width.

And there you have it. Just my 2 cents. Hope that helps those in need of antenna opinions.

Alex · Site Admin Joined: 19 Sep 2006 Posts: 1893

shooter64738 · EVDO User Joined: 07 Sep 2007 Posts: 41

I can show you a picture of the sheet metal but the antenna was not mine. It's silver at the bottom, had a big blue Sideways W on the can at the bottom looked like something else was written on there at one time but I didn't try to read it, and it wasn't magetic. There weren't any grounding aerials on the can, which I guess could have been a load coil. And it was an omni directional antenna. I have seen the antenna you're reffering to though, is the one with spikes the trucker, or is it vice versa?

shooter64738 · EVDO User Joined: 07 Sep 2007 Posts: 41

Yip! Looked just like that minus the aerials and the gold writing.

Alex · Site Admin Joined: 19 Sep 2006 Posts: 1893

shooter64738 · EVDO User Joined: 07 Sep 2007 Posts: 41

On the wilson site here:
http://www.wilsonelectronics.com/ViewProductB.php?ID=3

Or page 21 of this PDF
http://www.wpsantennas.com/pdf/catalog/Wilson_Cellular_Catalog_2007.PDF

These can apparently be ordered with or without mag mount. And my local Radio Shack has a Wilson omni (minus) the aerials, and it's not mag mount. The aerials only provide a ground plane for a non metallic surface. If you provide a ground plane for an antenna that has no aerials, it should work just fine. Which is why, I connected it to a large piece of metal.

Alex · Site Admin Joined: 19 Sep 2006 Posts: 1893

OK, i sit corrected. The NMO mount omni is simply not one WE sell.

shooter64738 · EVDO User Joined: 07 Sep 2007 Posts: 41

In either case, if your on the go, and you want a decent signal, omni is your best bet. And if my wife had her way, I wouldn't have this giant ugly dish on my roof! Smile

dondrm · EVDO User Joined: 06 Sep 2007 Posts: 64

Hi shooter, I really appreciate your antenna testing and those bi-quad building instructions in the other thread--a bi-quad & dish could end up being what makes the difference between EVDO and nada for me. I'll be trying a setup with the Wilson omni w/amp, but if that doesn't do it....

Sure wish you were here so we could test it out the way you did at your friend's. We're covered on the map but don't get more than 2 bars and 2K in or around the building, while 3 miles away we can get full bars and 1.8Mb.

I do have a couple of questions I'd like to ask you:

1) I wasn't sure what you meant by dual band in your instructions, but I'd guess you meant just slightly different frequencies for transmit and receive; I wonder how to figure out which frequencies to go for and what measurements to use based on that info--e.g. could you make a bi-quad that spans the full 800-1900 if you needed to? Probably not, I guess, but anyway...

2) I called Verizon and asked where the nearest towers were, and got an amazing bunch of stories--and that was after being bounced around to different departments like a pinball for about an hour spanning two different calls: e.g.:

"The nearest tower is 3.5 miles north by northeast of you in the city of Grants Pass" (which is 12.5 miles east of us); "You're covered on the map, definitely" (yes, as we mentioned half an hour ago, we know that); "The cities of A, B, C, X, and Y near you are covered" (OK, um, and the towers?); "The nearest tower is 11.5 miles from you" (I see, which direction?) "I can't tell you that, Sir" (Oh, so I should simply go around in circles and try all the directions until I get the best signal?) "Yes." (Thank you very much--have a good one) "You too."

So IOW I wonder how the heck to locate a Verizon tower, especially since I don't have a cell phone?

BTW if you still want to post photos and haven't found a good place, some people at a gemstone-hobby forum I visit where people are constantly posting lots of photos recommended photobucket.com, and I went there and set it up and posted some all in a few minutes--and it's free--but your instructions really don't need any photos.

Take it easy,
Don

Jim_in_VA · Posted: Sun Sep 30, 2007 3:51 pm Post subject:

dondrm, try http://www.antennasearch.com/ thats how I found the verizon towers around me. Some of the towers are owned by other companies and space is leased by verizon. If you click the details of the tower you can get more info such as email addresses that belong to Verizon...hence it is one of their cell sites. I pin-pointed mine that way.

shooter64738 · EVDO User Joined: 07 Sep 2007 Posts: 41

Don,
I think I have a place to host the photos, and I took a few more. Soon as I get a little time, I'll put them all up on the web.

You can build a dual band biquad, by making one square the prescribed 39.5mm and making the other square 38.5. I have yet to notice a real significant difference between the dual band, and the single band , but in theory the dual band should work better.

You can find the frequency ranges on the cards web site usually. I found the ranges for mine on the Sierra web site. There is a data sheeet for it listing the 1xRTT as transmit 824-849mhz receive 868-894mhz. Evdo transmits on 1850-1910mhz and receive is 1930-1990 mhz.

The anteana search site works good for locating a tower. Also you might try the tower structure search on the FCC web site. Usually a zip code will get you a group of towers, and you can narrow it down from there, which ones are verizon/sprint/alltel. A quick check on google earth with the Lat/Long numbers will give you a pretty close estimate of distance, and if there is hilly terrain between you.

dondrm · EVDO User Joined: 06 Sep 2007 Posts: 64

Thanks Jim and Shooter. That's good news about the photos, which I look forward to seeing, and about the bi-quad, which I look forward to making--I just pulled down an old Hughes dish that someone had left at this building before we came.... ;-)

I'd looked at those tower search sites before but didn't know whose towers were whose, and I'd read in some other forums that often a tower isn't registered and so won't show up on those maps, but I looked again AND called Verizon back, and this time they were very forthcoming and helpful--warm and friendly in fact.

So with their info and the search sites' info, we now know that there are 3 proximate towers and we know right where they are: Two of them show on the search maps and are Verizon's own, 1 of them 5 miles east and the other 10 miles south; the third, which isn't on the maps, is 3 1/4 miles north-northeast and is shared by Verizon with another owner/carrier ("so there can be interference").

I wonder in this case which would be better: whether it would be best to try to pull in as much as we can from all 3 towers with an omni, or whether we should de-emphasize the nearby tower and not bother with the far one and instead concentrate on the eastern 5-mile one with a directional antenna? I'm going to like pointing the bi-quad/dish in each of those directions.

I think we've got a direct line to all 3 towers from the roof, BTW, as far as hills and buildings are concerned; other than that, just a few of our own trees seem to be between us and the 2 nearest towers, just air and distance in the way of the far one--our building is taller than anything else around here and all 3 tower tops are at a higher elevation than the roof.

I'll keep checking back about those photos. Take care.

n6gn · Posted: Fri Oct 05, 2007 7:26 am Post subject:

shooter64738 · EVDO User Joined: 07 Sep 2007 Posts: 41

Don, sent you a private message have a look when you get a chance.

I echo n6gn's comments. Go for a single point, and avoid as much foliage as you can. Go for the stronger signal regardless, but it's probably going to be your nearest tower with the least LOS interference. If it's not don't worry, you can still likely get a good signal from your 5 mile tower with the clear sight.

dondrm · EVDO User Joined: 06 Sep 2007 Posts: 64

Valuable perspective, n6gn and shooter, and much appreciated.