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ArizonaSteve
join:2004-01-31
Apache Junction, AZ

ArizonaSteve

Member

External Antenna Success Stories?

I can only get a decent signal if I use a USB extension cable and place the unit in the window so I figured an external antenna on the roof would give me a good signal. I purchased a Wilson 5db gain dual-band antenna model 301103 from ebay that is supposed to work for Sprint PCS and put it on the roof but when it's plugged in it actually makes the signal WEAKER! They make a lot of claims for this antenna and state that it's supposed to pickup 800 & 1900 Mhz frequencies but it doesn't seem to get anything at all. Has anyone ran into this or actually got an antenna to work? Wilson is supposed to be a reputatable antenna company so I emailed them to ask why they are selling worthless antennas but got no reply so far. I also ordered a high gain 24 db yagi and can't wait to get that to see how it compares.

»cgi.ebay.com/ws/eBayISAP ··· 73487923
»cgi.ebay.com/ws/eBayISAP ··· 58813138
bcsman
join:2010-09-07
Capac, MI

bcsman

Member

Am on the fringe area for Sprint 3G coverage but went with the Virgin Mobile setup anyhow. Got a pretty weak signal, -100DB or less most of the time. It did help as you stated by using a USB cord and finding a window. Decided to try an external antenna and after much debate went with a parabolic grid dish and LM400 low loss cable. I mounted the dish on my 2 story farmhouse roof, TV antenna mast actually, and ran 50' of cable to my main computer. After firing it up and aiming while talking to my wife by the computer I was able to get 4 bars of signal and -62 DB on my Virgin Mobile control panel. Been VERY happy ever since. My problem isn't distance from the tower, but trees, trees, and more trees. I've read stories of folks who did just like me and didn't have as much success, but I can say it worked like a charm for me.....

I can tell you that antenna you purchased draws a signal from a 360 degree radius. If you are trying to train on a particular tower the yagi or parabolic dish are what you need....
tomupnorth
join:2005-01-14
UpperMidwest

tomupnorth to ArizonaSteve

Member

to ArizonaSteve
My experience is almost identical to bcsman's. The parabolic grid from geeks.com and 50' of LMR400 and even from four miles away I'm -51db and my Cradlepoint router says 100% signal.

I've had a couple of day-long outages in 3mos w/Virgin but overall it's been good, and wicked-fast compared to satellite.

MikeInIN
@sprintbbd.net

MikeInIN

Anon

I've tried to figure antennas out, it's one of the most complicated things I've ever tried to understand.

One thing I could understand was, the higher the gain of the antenna, the more directional it is, a 24db gain is HIGHLY directional, so you need to be pointing it RIGHT at your signal.

MikeInIn
@sprintbbd.net

MikeInIn to tomupnorth

Anon

to tomupnorth
I would also add, your 'gain' can be in the horizontal or vertical plane. think of it like taking a basketball and flattening it, that's what your antenna is doing to it's signal, it can flatten it in the vertical, or horizontal plane, so you gotta have it pointed at the tower, and it also has to be level with the tower, especially if you have a 24 db gain antenna, which sounds very sensitive.
ArizonaSteve
join:2004-01-31
Apache Junction, AZ

ArizonaSteve

Member

The high gain 24 db yagi didn't work either. There seems to be a lot of fraud in antenna sales out there. I tried both antennas on a spectrum analyzer and they don't pick up any signals compared to a cheap $5 magnet mount cellular antenna from the swapmeet that does pickup some signal.
The yagi didn't pickup anything on the Sprint PCS bands and turned out to be a UHF TV antenna they are selling as a cellphone antenna. I was going to send it back but it works so well for TV that I can pickup all the Phoenix and Tucson stations on the little thing so I'm going to keep it to use for that. LOL.
Another problem is the cheap, poorly made FME connectors that Wilson used to connect the antenna lead to the adapter for your device. I had to try 3 of them before I found one that fit properly. The first one had bad threads and wouldn't go on all the way, the 2nd one had a loose center pin that pushed in when I tried to connect it but the 3rd one finally fit. There's still no signal though so I can't recommend using Wilson antennas or any kind of antenna that has an FME connector.
For now I am using the USB dongle on the roof with a long USB cable. A stronger signal doesn't help the slow speed any but it doesn't get as many dropouts now.

Max Signal
Premium Member
join:2008-03-07
Buffalo, NY

Max Signal

Premium Member

The Cyfre equipment uses TNC connectors. Lots of success stories in these forums . Check out Jim's review
»evdotips.blogspot.com/20 ··· wed.html
ArizonaSteve
join:2004-01-31
Apache Junction, AZ

ArizonaSteve

Member

Wow, that guy got a much faster speed on Verizon using the booster. I suspest Verizon is faster to start with though, it doesn't seem to help Sprint to increase the signal strength. I've already got 4 bars and -71 db signal strength and it's still slow.
A high gain yagi might work well if it was actually cut to 1900Mhz and not just a UHF TV antenna. I'm thinking of getting a wi-fi yagi on ebay for $10 and modifying it to work on 1900Mhz. That would only require replacing the short elements with longer ones so all I would need is another piece of aluminum rod to use to make the elements.
Max Signal
Premium Member
join:2008-03-07
Buffalo, NY

Max Signal

Premium Member

If you are going to anything not involving an amplifier , get a parabolic grid . Jim has all the info you need on them at his site . WWW.EVDO-TIPS.COM . Do not use stuff made for wifi. There are lots of cheap but ineffective solutions in the antenna world , Some stuff is junk to be kind. Do some reading on Jim's site and he will point you in the right direction.

dib22
join:2002-01-27
Kansas City, MO

dib22

Member

said by Max Signal:

Do not use stuff made for wifi. There are lots of cheap but ineffective solutions in the antenna world , Some stuff is junk to be kind. Do some reading on Jim's site and he will point you in the right direction.

A wifi parabolic works just fine on sprint... even Jim's site concurs:
said by evdo-tips :

Many people have purchased a 2.4 GHz version to use on a 1.9 GHz (1900 MHz) EVDO network. Mainly due to the lower cost. The 2.4 version will work, the loss is less than one dB with the minor mis-match. Minimal indeed.

Max Signal
Premium Member
join:2008-03-07
Buffalo, NY

Max Signal

Premium Member

maybe fine with a 2.4 parabolic grid , but I would not refer to a wifi yagi which is what the poster mentioned

MikeIN
@sprintbbd.net

MikeIN

Anon

Transmit Band: 824.7-848.31MHz / 1851.25-1908.75MHz
Receive Band: 869.7-893.31MHz / 1931.25-1988.75MHz

These are the frequencies your MC760 uses. you can look this up on your mc760 owner's manual. you need a dual band antenna.

dib22
join:2002-01-27
Kansas City, MO

dib22

Member

said by MikeIN :

Transmit Band: 824.7-848.31MHz / 1851.25-1908.75MHz
Receive Band: 869.7-893.31MHz / 1931.25-1988.75MHz

These are the frequencies your MC760 uses. you can look this up on your mc760 owner's manual. you need a dual band antenna.

sprint only uses 1900... for a virgin mobile branded mc760 you would not need a dual band antenna... now if you plan one day to use a verizon device then you could get a dual band antenna and be future ready I suppose.
bcsman
join:2010-09-07
Capac, MI

bcsman to ArizonaSteve

Member

to ArizonaSteve
Just remember for any of you trying an external or roof mounted antenna, if your cable length is going to be more than 20-25' I would consider purchasing the low loss cable, LM400 or equivalent.

Also remember if you are using coax laying around for your TV antenna it is NOT the correct impedance. TV antenna coax is rated for 75 ohms, but the coax needed for this operation should be rated at 50 ohms. If you are using TV antenna coax it will definitely degrade any signal you receive.
ArizonaSteve
join:2004-01-31
Apache Junction, AZ

ArizonaSteve to dib22

Member

to dib22
I don't know where you got the idea that sprint only uses 1900 but that's not true since it's monitoring 2 different frequencies on 2 antenna inputs. Check ##DEBUG and look at the line called Rx Power. I think 1X uses 850 and EVDO uses 1900 but I'm not sure. Anyway, an 850Mhz antenna makes one reading go up and the other one go down while a 1900Nhz antenna has just the opposite effect so it doesn't work correctly unless a dual band antenna is used.

dib22
join:2002-01-27
Kansas City, MO

dib22

Member

said by ArizonaSteve:

I don't know where you got the idea that sprint only uses 1900 but that's not true since it's monitoring 2 different frequencies on 2 antenna inputs. Check ##DEBUG and look at the line called Rx Power. I think 1X uses 850 and EVDO uses 1900 but I'm not sure. Anyway, an 850Mhz antenna makes one reading go up and the other one go down while a 1900Nhz antenna has just the opposite effect so it doesn't work correctly unless a dual band antenna is used.

the term "1900mhz" is how we refer to the spaces that sprint controls in the usa... it is actually several frequencies around the 1900mhz mark.

verizon has a mixed network where some areas are on what we call "800mhz" and other areas use "1900mhz" even though yes it is several frequencies in the 800 and 1900 range.

now if you were on a sprint account it could technically roam onto a verizon 800mhz system if the card supports it... but a VM device will never roam onto a non sprint access point.

hope that clears it up!

(technically sprint has 1900mhz, 2500mhz-2700mhz and even a few random 800mhz for the old nextel iden network... but CDMA/evdo broadband is always 1900mhz in the usa on their network at this time)

MikeInIN
@sprintbbd.net

MikeInIN to dib22

Anon

to dib22
the VM card uses the 800-900 Mhz frequency for the CDMA or 1Xrt mode. When you are at around the .14 Mb range, it will switch to xrt mode, so yes it does use these frequencies. It will use whichever is getting a better signal.

The EVdo frequencies are 1800-1990 and those are the ones you want.

MikeInIN

MikeInIN to dib22

Anon

to dib22
Arizona Steve, if you are using such powerful antennas, you may be getting TOO MUCH signal. If you are getting too much signal, your Virgin mobile modem will simply ignore the external antenna.

Also, you can't plug the antenna in while the USB modem is plugged in, you have to unplug the modem, THEN insert the antenna, then plug it back into the usb port, or it will ignore the external antenna. That didn't necessarily seem obvious to me.

The Virgin Mobile uses different sets of power circuits, it has a set of circuits it uses when it's gettin a very strong signal, close to a tower and a set of more receptive circuits , for weaker signals, and when you need more transmitting power to reach the tower. This is so a strong signal doesn't fry your fragile circuits, or distort their waveforms and all that complicated, mind-boggling stuff.
Expand your moderator at work
Max Signal
Premium Member
join:2008-03-07
Buffalo, NY

Max Signal

Premium Member

Re: External Antenna Success Stories?

Best site for help on antennas is www.evdo-tips.com . Jim has done lots of research and testing . It is a really good info site.

dib22
join:2002-01-27
Kansas City, MO

dib22 to MikeInIN

Member

to MikeInIN
said by MikeInIN:

the VM card uses the 800-900 Mhz frequency for the CDMA or 1Xrt mode. When you are at around the .14 Mb range, it will switch to xrt mode, so yes it does use these frequencies. It will use whichever is getting a better signal.
The EVdo frequencies are 1800-1990 and those are the ones you want.

incorrect... sprint's cdma network is only 1900... never ever anything else... this includes 1xrtt and evdo.

verizon has a mixed cdma network so on verizon yes you will see 800 or 1900 depending on the area... sprint's network wasn't piecemealed together like verizons was.

signalhelp
@verizon.net

signalhelp to ArizonaSteve

Anon

to ArizonaSteve
You are buying antennas that have horrible cables. The signal is lost before it even reaches the device. Ever notice how cable tv coax is super thick compared to what came with what you bought? And tv cable is usually only good for up to 1Ghz. 1.9Ghz is almost twice that.
The solution? Buy one with a connector and use lower loss cable.
If you're not using an amp, I'd recommend you use lmr400 cable for runs over 10ft. RG58 is good for less than that or with amp.
My setup had 23ft of RG58, an amp, and the same antenna below on 2nd story (MUST be outside).

»powerfulsignal.com/wilso ··· nna.aspx
I bought my antenna from them, not the cable so I have no idea of its quality. But looks the same and prices are very fair compared to wpsantennas.