Any hope for me?

Charlie_r_m · EVDO Newbie Joined: 10 Oct 2007 Posts: 8

I'm 10 miles from the alltel tower in Columbus, MS. I can drive down the road about 5 miles and pick up the EVDO signal pretty strong. I could barely pick up the 1xrtt signal before buying an antenna. After installing the yagi I can get 4 bars (-82db) of 1xrtt. Is there a chance to pull in the EVDO?

CraigCraig · EVDO Heavy User Joined: 15 May 2007 Posts: 141

Do you get any EVDO signal at all (even if you can't connect) when using your yagi?

When you connect using 1xrtt are you roaming or are you positively using Alltel?

How much time is left on your Alltel contract?

Charlie_r_m · EVDO Newbie Joined: 10 Oct 2007 Posts: 8

The evdo signal will pick up slightly (moving from 97-115) but is unusable.

I think i am using Alltel. There are no sprint towers around according to a tower searching site.

The trial is up on it. It took 12 days to get the antenna from the place I ordered it. I didn't get it at 3gstore...some other site

I've got detailed info on a blog I'm working on but I can't post links here.

CraigCraig · EVDO Heavy User Joined: 15 May 2007 Posts: 141

It looks like you could get EVDO using your Yagi and an amp.

I have a Wilson 3 Watt Bi-Directional Dual-Band, the kind they sell at the 3G store and am happy with it. I haven't had signal strengths like you have to deal with but it helps to pull in weak signals and increase speed for me when I need it.

You could always try the Wilson amp from the 3G store and if it doesn't work, return it. Talk to the guys at 3G before you order it to make sure that they think it would work for you too and to get the right adapters, cable, etc. as required.

Charlie_r_m · EVDO Newbie Joined: 10 Oct 2007 Posts: 8

Thanks for the help. I may try an amp. It's just odd how it will pick up and evdo signal off and on but doesn't let me connect at all. I suppose I could take my antenna down and drive down the road and see if it picks up the evdo signal. I'm almost to the point that I think there is something wrong with it. It's not a brand name item like Wilson. If you want to get a better idea about what I'm dealing with you can go to my site. mississippigeek. The end is com.

I did contact 3gstore and they got back at me but never replied back after my response to their question.

Thanks

CraigCraig · EVDO Heavy User Joined: 15 May 2007 Posts: 141

Well a 97-115 signal is pretty weak and if it is very unstable that may be why your card won't connect.

Try the amp I suggested above as the worst thing that could happen is that it doesn't work for you and you have to return it.

I don't know if you've spent time getting the best signal from your Yagi but I've used a friends Yagi in the boondocks and found I had to spend about 15 minutes "fine tuning" its orientation to achieve the best signal strength.

I noticed you have an expensive "chicken shade" (from your website picts) so here is a link to a guy that used a "chicken shade" to pull in an EVDO signal the last two posts by oldbull in the thread give the best info (and I don't think he was using an amp--just "spare" parts.)

http://www.evdoforums.com/viewtopic.php?t=2879&highlight=

Charlie_r_m · EVDO Newbie Joined: 10 Oct 2007 Posts: 8

Thanks a lot man for the advice. I've been playing with the idea of modifying the "chicken shade". Even if I decided to go back with wildblue I would pretty much have to buy new equipment seeing how the trias go bad every few months and I'd need someone to realign the dish. Either way, the satellite is closed for my area now come to think of it. I probably will try an amp first though to try to save some of the 60 bucks investment I have in that yagi.

CraigCraig · EVDO Heavy User Joined: 15 May 2007 Posts: 141

Charlie_r_m · EVDO Newbie Joined: 10 Oct 2007 Posts: 8

What is the loss per foot of RG-58? I found a coax calculator on the Net that says it's about .221 per foot @1900mhz. That would mean I'm losing almost 7.28dbm with the 33ft of cable. I have 20 feet of LMR400 I can use from my wifi parabolic antenna. According to that calculator I would only lose 1.17dbm for the 20 feet @1900mhz. Do those numbers sound right for loss per foot? RG-58 = .221 and LMR400 = 0.058. Of course that's at 1900mhz. At 800mhz it is a little less: 0.036 for the LMR400 and 0.127 for the RG-58 per foot. So, 4.19dbm at 33ft of RG-58 and .73dbm at 20 feet of LMR400. Either way, I would gain about 3dbm on 1xrtt and 6dbm at 1900mhz.

CraigCraig · EVDO Heavy User Joined: 15 May 2007 Posts: 141

Charlie, that sounds about right regarding the cable loss calculations. I think you'd lose about 1/2 a db on the connection between the two but I am not too knowledgeable in that area.

There are some very knowledgeable people on this forum and if you post a new topic regarding cable loss you are sure to get some good replies.

Oldbull · EVDO Fledgling Joined: 05 Oct 2005 Posts: 24

Good luck on getting that evdo signal Charlie. Since you have the WB dish available, I would set it up and point it at the the closest tower. Pick up a cheap panel antenna to hook to your card, take your laptop outside and wave the antenna around in the transponder area and see what kind of signal you can get. Will only waste about 15 bucks and and afternoon of your time.

Charlie_r_m · EVDO Newbie Joined: 10 Oct 2007 Posts: 8

Thanks for all the help and encouragement but I think I'm about done with
evdo for awhile. I just don't understand what's going on with it. I can travel 2-4 or so miles down the road depending on the weather and pick up evdo enough to use it but I can't get a flipping thing with an antenna 30 feet in the air. I've fine tuned it several times and can't get a usable evdo signal. One thing i have noticed is this connection software of alltel's is crap. Right now i'm in the middle of town and it's showing 0 bars but i have a signal of 77-83 HDR. It's really impossible to fine tune something when you can't see a "real" signal. Even in field test mode it's flaky. I've about had all the headache i can stand. To top it off I used letstalk.com to buy the card and service so I'm going to be looking at 500+ bucks to cancel after I pay their contract plus alltels. Ah well, that's what I get for thinking I could get a low ping, dsl like connection out where I live. hah. Next thing that'll happen is I'll probably end up with a $2000 roaming bill or something. Even though the software says nothing about roaming.

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

Hi Oldbull,

So your setup's success survived the leaves of spring and summer! :-) It's heartening to hear your recommendation going strong.

I've been meaning to ask you for some time about the 'inexpensive panel antenna' in that neat photo of your stuff clamped onto a deck railing among the pines (10/23/06 in the 'trying to pull in a difficult signal' thread): What antenna is that and where'd you get it? It seems like all the panel antennas I've seen are expensive, and most of them are billed as indoor types. And I'd guess it's dual band, right?

I was working on some bi-quad antennas to try but was unable to determine which band to go with, especially after a Verizon tech I spoke to insisted that Verizon uses both bands for EVDO and that the towers switch between them, at least our towers. So it looks like I'll need a dual band if that tech isn't mistaken--though he did seem knowledgeable and to know exactly what I was talking about. (I'm thinking of getting a Novatel V620 from eBay just to do testing, so that I can determine the sort of signal I'm getting before I re-activate my Verizon account with a new modem. That might also tell me which band it's using. The phone I'm currently testing with shows a good strong signal with some setups, but it's definitely in the 850 band and might not translate into EVDO.)

Again, great photo.

CraigCraig · EVDO Heavy User Joined: 15 May 2007 Posts: 141

Oldbull · EVDO Fledgling Joined: 05 Oct 2005 Posts: 24

Hey dondrm,

Actually I never got to test the unit with the full bloom of spring leaves. Shortly after I got everything working in a reasonably stable manner, after 6 months of effort I might add, Sprint finally lit up the tower about 2-3 miles from my house and I was able to get great EVDO. Two or three months after that Virginia Broadband offered wireless in my area and I purchased a plan from them, currently I run both systems, me and the wife use VBB and the kids share the Sprint account through the Linksys EVDO router.

I must say that I have been really happy with the VBB Wireless, ping is usually between 50 and 100. Our plan only allows 7 gig a month download so that's fine for me and the wife and the kids use the unlimited Sprint to do all their Youtoobing. Kind of expensive for internet but beats the heck out of dial-up.

Anyway, back to your questions. I guess "cheap flat panel" may mean different things to different people, for me it was about $50.00. I considered this cheap for a 10 to 12 db antenna that seemed to be well made and worked nicely. Many of the "parts" in my quest to pull in EVDO cost well over $200.00 ( Amp, repeater and router...a $60 yagi that never pulled in anything and about $70 for a Wilson trucker ) it all adds up fast. I don't recall where I purchased this particular antenna but I will try to find the receipt.

I would also like to pass on a neat observation I made after VBB installed their wireless setup. After VBB set up a really nice 6 or 7 foot long yagi on my roof and connected it to the modem in my living room I noticed the cable ended in a nice N type connector. I checked my spare part box and was able to find the proper fittings and cables that would allow me to connect the VBB yagi to my EVDO card. You know I just had to do it. The yagi was already pointing within a few degrees of the Sprint tower, guess what, that 2.4 ghz wifi antenna gave me a rock solid 65 - 68 db signal on the EVDO card. I was getting about 85 without any antenna. I did a few test runs on the download test sites and everything worked like a champ for the hour or so that I played with it.

I truly can't remember if I read something about this in the forums here first or if I just tried it on a whim, but somewhere buried in the forums someone does talks about using wifi 2.4 ghz parabolic antennas and it being possible to get good results with EVDO. There seem to be a lot of those available at a decent price on the internet and if I was going to mess with trying to pull in a long distant EVDO signal again I would definitely think about giving one a try. Why mess with a Direct TV dish and a 1.9 ghz flat panel when a nice big, cheap 2.4 ghz parabolic may work just as well.

Of course all of this has been by the "seat of my pants", I do understand some of the basics about how all this stuff works but I don't pretend to be any type of expert. I'm sure others here can give some detailed info about why these things may or may not work, I just like to "fiddle" around with stuff.

Good luck.