Trying to pull in a difficult signal

Oldbull · EVDO Fledgling Joined: 05 Oct 2005 Posts: 25

First off let me thank everyone responsible for this site and the information it contains. During the past year and a half I have tried to follow the development of EVDO closely, fortunately, I discovered this site soon after visiting the Robert Kim (aka The Debil) site. I'm soooo glad I did not spend much time there.

Hopefully, now I can stop lurking and share some of my recent adventures in EVDO reception with everyone. Maybe it can help someone.

I'll start with a little background. Currently I have a Sprint contract and use the Merlin 620 data card in a Dell 9300 Inspiron notebook. The closest Sprint tower to my home is apx. 2 miles to the north and the closest Sprint EVDO active tower is apx.10 miles north of that tower, I do not have a direct LOS to either tower. Many trees and dense foliage surrounds my home and the terrain is gently rolling hills. Not the best scenario to work with.

Many of the trees north of my home are very tall pines, the tops are foliage heavy but the middle portions are relatively clear and offer a "shot" at the horizon. I would never be able to economically raise a tower high enough to pull in a clean signal from above them so my goal currently is to aim the antennas under the heavy foliage towards the cell towers.

My laptop, located at my desk in the south end of the house, without an external antenna attached, normally displays a signal of -98 to -103 db. Surprisingly I get decent 1xRTT performance of 120ish down and 50ish up with this signal.

My goal is to see how low I can get my 1xRTT signal and hopefully to be able to get a usable EVDO signal. In the next few weeks hopefully I will have some useful information to share for those interested.

I will be using the following equipment :

CA-819 Dual Band Amp - Maximum Signal

14 D 9 Element Yagi - Maximum Signal

Clear Voice 1900 Cellular Repeater - Telecom Technologies

Arc Freedom Antenna - Don't remember where I got this.

Home Brew 1900 mhz Cantenna and BiQuad Antenna

Wish me luck !!

horsessmellfunny · Posted: Wed Jul 19, 2006 10:30 pm Post subject:

Ah you sound just like me! Welcome to my world my friend! Anyways, heres a tip. Take that 1900 MHZ cantenna you have there. Get a satellite dish (tv), mount your cantenna in the middle, and aim to the middle as best as you can. Aim the satellite in the direction of the tower, and see what you can get. A typical satellite/cantenna rig will do about 10 miles point to point line of sight. I have done some "experimenting" with this myself. I will eventualyl get pics and more about it up on my website when I get a chance. Let me know how things go!

Oldbull · EVDO Fledgling Joined: 05 Oct 2005 Posts: 25

Here are the results from my first round of tests.

Sprint 620 without external antenna. Signal between -98 and -104 dBm

Download tests from Frontier.net up/down 122/ 52 57/47 115/14 120/30 120/33

EVDO Signal.......NO

Sprint 620 with Arc Freedom antenna. Signal between -95 and -100 dBm

Download tests from Frontier.net up/down 51/47 121/81 119/53 122/33 125/48

EVDO Signal.......NO

Sprint 620, CA-819 Amp and Arc Freedom antenna. Signal between -83 and -93 dBm

Download tests from Frontier.net up/down 121/41 119/35 122/39 122/112 123/32

EVDO Signal.......YES Able to connect to EVDO briefly and start the web browser, then dropped connection.

All these tests were run at my desk inside the house with the Arc freedom antenna (also sitting on the desk) pointing towards the cell towers to the north.

The signal strength appears to fluctuate a lot, even with the Amp in use. As I stated in the opening message, I have a lot of trees around the house. Even with the signal fluctuation, the connection with the CA-819 Amp seemed very stable and evened out the performance on Frontier.net. Briefly I was even able to connect to the EVDO tower that is almost 12 miles away, even though all components were inside the house.

The CA-819 Amp from Maximum Signal appears to work well, even paired with a low end antenna.

Over the weekend I'll try to get some info using the Clear Voice 1900 Cellular Repeater.

Jimincalifornia · EVDO User Joined: 25 Sep 2005 Posts: 72

http://www.evdoforums.com/viewtopic.phpt=1887

My experience with just a pair of window stickums and the CA-819 has been phenomenal, punching through a metal skinned, metal framed motorhome.

Oldbull · EVDO Fledgling Joined: 05 Oct 2005 Posts: 25

Ok, getting back with some results from the Clear Voice 1900 cellular repeater.

Originally I had very high hopes for this unit. I did a quick hookup and my signal dropped from about -100dBm to -78 dBm...I was like WOWWWZA. Later when I was ready to take some detailed notes the signal was nowhere close to what I had originally received. I checked and double checked all the connections but -88 dBm was about the best I could get, maybe the wind was just blowing in the right direction the first day.

A bit about the unit first:

• Supports up to 20 simultaneous callers.
• Up to 2,500 Square Feet Coverage (depends upon outdoor signal strength, building construction, installation care).
• Indicator lights for easy directional antenna alignment.
• 55dB signal gain, 7dBm maximum signal power.

Kit Contains:

• Clear Voice 1900 Repeater amplifier unit.
• Directional reception patch antenna. ( apx 4' wide by 5" tall )
• Monopole rebroadcast antenna.
• 30 foot, 50-ohm antenna cable. ( Looks similar to RG58 )
• Power adapter.
• All necessary attachments.
• Installation manual.

The unit was purchased from Cellboosterstore.com for $259.00 and there is a 14 day trial in which you can return for a full refund. I am in not in any way affiliated with anyone selling these units.

First thing I did was to mount the small panel antenna on the north side of my house. 30 foot of cable is supplied with the kit. This was enough to allow me to mount the repeater amplifier unit on an interior wall within the house, I selected a spot that would require the signal to penetrate at least 1 wall before it reached my computer, and mounted the unit at about the 6' level.

The Clear Voice 1900 Repeater has a handy 10 bar LED signal strength indicator on the front of the unit. The instruction manual states that the first and last bar are not really used for the signal strength indication. Only 1 bar means you were not getting a signal and the 10th bar indicates you are getting too much feedback from the external antenna. Optimum results would be obtained if 5 or 6 of the middle 8 LED's for indicating signal strength were lit.

The best signal strength I could obtain was only 2-3 bars as indicated on the signal strength indicator, laptop was about 20 feet from the repeater and the signal was passing through 1 interior sheetrock wall.

Sprint 620...........CV-1900..........Supplied Panel Antenna. Signal between -88 and -95 dBm

Download tests from Frontiernet.net down/up 119/36 108/67 94/44 120/37 119/47

EVDO Signal.......NO

Sprint 620 with Arc Freedom antenna......... CV-1900..........Supplied Panel Antenna.
Signal between -85 and -90 dBm

Download tests from Frontiernet.net down/up 122/46 123/33 119/36 121/65 118/83

EVDO Signal.......NO

Next I removed the cable from the inside repeater and hooked it up to the CA-819 amp while continuing to use the external mounted panel antenna supplied with the CV-1900.

Signal between -78 and -84 dBm

Download tests from Frontiernet.net down/up 127/42 121/41 122/36 121/76 115/80

EVDO Signal.......NO

I was not able to receive the required signal needed by the CV-1900, ( 2-3 bars instead of 5-6 ) it performed well enough considering the weak signal. I think this unit can be useful for those that get a decent signal and would like to increase their cell phone signal as well as their EVDO signal within a home. It just did not perform the job I needed it to do. Like I stated above, I get a really crappy signal. I will keep the unit though, currently I have Verizon cell service, it will come in handy when I shift everything over to Sprint.

I don't seem to have accomplished much with all this. I'm partial to the CA-819 amp though, but I really need to find a good antenna to mate it with. I've tried it with the Yagi from Maximum Signal but can't seem to hit anything with it. I'm really curious how it would work with a high end panel antenna and some decent low loss cable instead of the RG58 I been using.

Maybe more another day if I feel up to fooling with this stuff again.

Hope someone gets something from all this.

kaefer · EVDO User Joined: 05 Dec 2005 Posts: 66

You could try hooking up the repeater and amp in series:

http://www.evdoforums.com/about2551.html

Oldbull · EVDO Fledgling Joined: 05 Oct 2005 Posts: 25

Well, this update has been a long time coming.

I’m happy to report that finally I have achieved some success at gathering in the elusive EVDO signal. The best I can estimate the distance to closest EVDO tower is 10 to 12 miles. Currently I am displaying a signal of 90 to 92 dBm on the Sprint Connection Manager using an old satellite dish and a 13 dBi panel antenna.

I’ve included a picture so that all can see that it’s a pretty simple setup. I’ve tried quite a few things in the last couple of months, homemade cantenna and biquad antennas, solo and with the satellite dish. All worked and allowed a usable signal but using the inexpensive panel antenna actually gave the best signal and seemed easier to aim.

Of course, I think my biggest gain in signal came from all the leaves falling from the trees, I figure I’m in almost broadband heaven until about mid-march. I’m in a “future” EVDO expansion area for Sprint, I just have no idea of what their idea of “future” is.

Download speeds and kinda flaky, I’m all over the place from 500k to 800k. Upload speeds are espicially bad 20 to 40k usually. But, let me tell you, ANYTHING, is better than my dialup which appears to be 28.8 at the best of times.

In the photo I’m using RG-58 and as I type the UPS guy appears to be dropping off my LMR400 coax, hopefully this will help.

***** Darn, I don’t know how to get a picture to display here : (

[/img]

J.C. Roberts · EVDO Fledgling Joined: 14 Nov 2006 Posts: 14

As for adding an image to your post, you need a place to host the image. You can upload it to something like

http://imageshack.us

You can then either post a text link to it or you can embed the picture by using the "Img" button when posting.

kaefer · EVDO User Joined: 05 Dec 2005 Posts: 66

Oldbull · EVDO Fledgling Joined: 05 Oct 2005 Posts: 25

Ok, think this works.

[img]

[/img]

fordrhs41 · EVDO User Joined: 29 Jan 2007 Posts: 93

[quote="Oldbull"]Well, this update has been a long time coming.

Some deleted for brevity

I’m happy to report that finally I have achieved some success at gathering in the elusive EVDO signal.

***** Darn, I don’t know how to get a picture to display here : (

You are not alone and I have seen a few pictures here and I would appreciate someone explaining how a picture/screenshot can be added to a message.
Ford

fourmonks · EVDO Newbie Joined: 04 Dec 2007 Posts: 2

Can you give me some information on the brand of flat panel antenna you used? I am going to attempt a similar dish antenna set up for Verizon rboadband. My closest EVDO Verizon tower is a bit closer than yours, perhaps it will work. Thanks in advance.

powrby4d · EVDO User Joined: 24 Dec 2007 Posts: 45

so Oldbull, was the panel antenna a dual band as the CA-819 manufacturer states must be used or it will harm the amp, and if not a dual band and you stuck with that configuration did it ever cause any problems with your amp?

wavrider · EVDO Fledgling Joined: 14 Jun 2008 Posts: 19

With the size of that flat panel antenna you may getbetter peformance from a bigger parabolic reflector, something around the size of a hughes net or primestar dish.

I am using a bi quad to feed a hughes net and getting a 27dbi gain over just the compass 597 card.

I was first using rg6 which is a 75ohm cable and got -85 dbi signal.

I then ordered and recieved some lmr400 and am getting a -77dbi signal

With just the compass 597 card i get a -104 signal.

tower is 3.3 miles away but targeting the NW according to sprint technical support, I am on the SE side of tower.