Need brilliant ideas for very difficult signal situation

thebordella · EVDO User Joined: 12 Mar 2007 Posts: 26

Hi,

Advance apologies for your patience as I describe this situation. I know there are many experienced gurus in this forum and I am pleading for your wisdom!

Great, dark forces have conspired to create a broadband blackhole around my house. No cable, no dsl, and the only wireless available is Verizon evdo. A neighbor who lives a half mile away on a hill gets an excellent signal; unfortunately, I am not on a hill. I am way down low behind the hill. The heavily forested hill.

I can limp along with NationalAccess and pull some marginal EVDO signals with an external antenna -- as in, weaker than -108 -- but it is not reliable.

Here is a link to a rough diagram of the property.

The problem is that the areas marked "forest" which bound the land are treed heavily with 70+ foot tall evergreens. I do not have the ability or resources to build a mast or tower that can top these. Anywhere in the "lawn" area is dwarfed by the forest -- even the roof.

Notice the public street. If I walk into the street from the property, the signal literally jumps to -96db or better. Unfortunately, I can't mount my antenna in the street!

I have the following gear: Verizon USB720 modem, 150 feet of Wilson 9913 ultra low loss cable (1 50 foot, 1 100 foot, with appropriate connectors), and a Wilson Trucker omni antenna, and 1 telescoping 28 foot jackite pole. I've spent two frustrating days trying to set this stuff up in the strip of forest beside the public road. After many hours of cuts, scrapes, and bruises (don't plant a tree this arbor day!), I'm not getting the progress I hoped for.

Unfortunately, I cannot mount the pole on the clear side of the forest strip because that is public land (a ditch, actually). The best I can do is get to the very very edge of forest. I have seen improvement, although very location sensitive, but it is still very asymmetrical -- good download, bad upload. (As in, 700kbps down, 20kbps up, with an rssi around -101 to -104).

I need ideas.

One idea is to "cheat" -- try and use a horizontal crossbar to cantilever the antenna into the public space by the road (but not over the road). This would be pretty conspicuous, but this is a rather rural area.

What about replacing the omni with a directional antenna? Might this be a better way to capture the sliver of signal that is shooting through these trees?

If I use a directional, how would you compare a typical Wilson yagi with, say, a 24 dbi 2.4ghz "wifi" grid parabola? I read on another forum here that the 2.4ghz wifi mesh antenna can actually produce good results for PCS, albeit with slight loss due to being near 1.9ghz. Basically, do you think the weak point in this setup is the omni?

It is difficult to mount anything with much weight on the pole since it tends to flex. The omni is quite lightweight, so it can be mounted to the tip of the pole with simple duct tape.

PS. I do not want to consider an amplifier, because of the $$, and the possibility that this setup is temporary (house is for sale...can you guess why?... want it!?).

Apologies for the long email. This situation is driving me crazy. A good signal is within reach, but I can't reach it! All I have to do is walk across the #!?@ street!

thanks for your patience and advice!
-Aaron

jackrodgers · EVDO Addict Joined: 23 Mar 2006 Posts: 1131

Weather balloon...
See Alex's battery operated CradlePoint wifi.
Long String

n6gn · Posted: Wed Oct 10, 2007 9:42 pm Post subject:

Figuring out how to mount the $50 dish well is probably the most bang for your buck.

A WiFi dish, if you can maintain it pointed correctly, will probably net you >16 dB improvement. Going to 150' (assuming you need all the length) of LMR400 instead of 9913 will probably net you another 9 dB.

Anything you can do to reduce the amount of foliage is likely to help. Increase height, mount on the 'far side' of the tree etc. Doing this *has* to be consistent with keeping it pointed accurately in weather, wind etc. Going higher with a dish seems problematic because tops of trees sway. It could be that the omni on a pole sticking out above tree top would do it for you though. If that's viable, you might consider springing for LMR400 and trying that before the dish. Sounds like more scraping and bruises to try it though Sad

n6gn

thebordella · EVDO User Joined: 12 Mar 2007 Posts: 26

Thanks for the ideas, n6gn. I may try the wifi antenna.

Let me ask a question to clarify about cable loss. You mention the low loss of LMR400. According to this chart, at 1900mhz the LMR is rated at just over 5.7db loss per 100 feet:

http://www.timesmicrowave.com/content/pdf/lmr/22-25.pdf

According to reference I've found elsewhere, the Wilson 9913 ultra low loss cable supposedly is rated at 4db of loss per 100 feet. For example, this is mentioned here (albeit, not an official source, but found elsewhere, too):

http://www.howardforums.com/archive/topic/360608-1.html

Am I misunderstanding. Just wanted to clarify, since you suggest a big potential gain with LMR400 vs. the 9913 ultra low loss I'm using now.

thanks!

n6gn · Posted: Thu Oct 11, 2007 9:27 am Post subject: