OnStar antenna as cellphone antenna

cody_s

Well-Known Member
#1
Curious if anyone has tried using the roof mounted OnStar antenna as a cellular phone antenna. I don't subscribe to, nor plan to subscribe to OnStar, and I realize the antenna is basically a cellular antenna. I just don't know if it's possible to rig it to amplify a cell phone signal though. Any thoughts?
 
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cody_s

cody_s

Well-Known Member
#3
the roadie said:
Do you have cell signal strength issues now?

Mostly, if you need an amplifier, an antenna only isn't the solution. Google for Wilson cell booster.
Not really, I just thought it would possibly help get a stronger signal when offroading.
 

WarGawd

Well-Known Member
#4
Can I ask what phone you have and who your provider is currently (ie what network type - GSM or CDMA)? I have a few thoughts on the subject and a couple vague memories that I might be able to use to prompt roadie a bit further, but I'd rather not start rambling on without a bit more info.
 
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cody_s

cody_s

Well-Known Member
#5
WarGawd said:
Can I ask what phone you have and who your provider is currently (ie what network type - GSM or CDMA)? I have a few thoughts on the subject and a couple vague memories that I might be able to use to prompt roadie a bit further, but I'd rather not start rambling on without a bit more info.
Using a Motorola Droid Razr through Verizon, so it's a CDMA.
 

RayVoy

Well-Known Member
#6
cody_s said:
Using a Motorola Droid Razr through Verizon, so it's a CDMA.
CDMA was the old network for companies like Verizon (and Bell in Canada); today, the data requirements for cell phones are driving the network technology. LTE is the new standard for data communication; originally a 3G product that developed from EDGE, it is now being marketed as the new 4G standard.

LTE was designed for the GSM networks, requiring the CDMA carriers to replace the complete network if they wish to convert to full LTE..........expensive.

To save the cost of converting (and the spectrum problems of every carrier being rooted in voice GSM) the CDMA guys are looking at things like Voice over LTE. The likely scenario, for the short term, will see the LTE phones fall back to 2G CDMA during voice calls.

Why I'm I expounding upon this, IDK, for the short term voice will still be over GSM, or CDMA and the Onstar antenna is bigger than the antenna in your handheld, letting us think it should increase the signal strength. However, they are probably not compatible. You would need one of two methods of connecting. An adapter that would be "hard wired" (using a jack) to your phone; or a wireless adapter that would act as a signal repeater.
 

The_Roadie

Founding Member
Lifetime VIP Supporter
#7
For way offroad in mountainous areas, get a ham license and a 2M rig, then join the local repeater club and know the frequencies they operate at.

For way, way offroad 2-way comm, own or rent a sat phone. Nothing else will do.

For way, way offroad solo trips, do what a lot of us do and get a SPOT beacon. If I was going to upgrade from SPOT right now, the right technology is the Delorme InReach system.

If you have a serious need for reliable offroad comm (checking to see what web site I'm on right now) lashing up any sort of passive antenna without an amplifier is worthless. Cell phones no longer have an external antenna connector for a reason.
 
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cody_s

cody_s

Well-Known Member
#8
Makes sense, thanks for all the input.
the roadie said:
For way offroad in mountainous areas, get a ham license and a 2M rig, then join the local repeater club and know the frequencies they operate at.
Yeah, I've been meaning to get a technicians license, time to start studying :smile:
 

WarGawd

Well-Known Member
#9
It's irrelevant now, other people seem to have addressed you question better.

I have Onstar, and a cell package thru them. I know it runs over the Bell CDMA network in Canada. I also noticed my antenna was a fair bit smaller that some later model year GMs which had me wondering what the nature of the change was. I also have learned roadie is a EE, and might have had valuable input on the subject of impedance matching/mismatching for the types of antennae designs used in modern phones for the different frequency bands.

I was also thinking along the lines that, if your GSM phone was experiencing reception problems in a particular spot, there may have been some merit for activating CDMA based Onstar calling, as different providers have different infrastructures and tower locations - IE maybe you'd be lucky enough to be closer to a CDMA tower when your GSM reception failed.

Anyway, it was mostly just thinking out loud on my part - if your CDMA phone doesn't have good reception, your CDMA-based Onstar antenna isn't likely to experience anything better.
 
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cody_s

cody_s

Well-Known Member
#10
WarGawd said:
It's irrelevant now, other people seem to have addressed you question better.

I have Onstar, and a cell package thru them. I know it runs over the Bell CDMA network in Canada. I also noticed my antenna was a fair bit smaller that some later model year GMs which had me wondering what the nature of the change was. I also have learned roadie is a EE, and might have had valuable input on the subject of impedance matching/mismatching for the types of antennae designs used in modern phones for the different frequency bands.

I was also thinking along the lines that, if your GSM phone was experiencing reception problems in a particular spot, there may have been some merit for activating CDMA based Onstar calling, as different providers have different infrastructures and tower locations - IE maybe you'd be lucky enough to be closer to a CDMA tower when your GSM reception failed.

Anyway, it was mostly just thinking out loud on my part - if your CDMA phone doesn't have good reception, your CDMA-based Onstar antenna isn't likely to experience anything better.
Yeah, well it was more of a, "I wonder if I could put this antenna to some sort of practical use" thing. My phone gets decent reception, just not as good if I'm offroad up in the mountains or something. But as Roadie pointed out, there's plenty of more practical alternatives than using the OnStar antenna. I've been looking into getting a HAM license anyway for communications when storm spotting, so that's probably what I'll end up going with.
 

djthumper

Administrator
#11
cody_s said:
Yeah, well it was more of a, "I wonder if I could put this antenna to some sort of practical use" thing. My phone gets decent reception, just not as good if I'm offroad up in the mountains or something. But as Roadie pointed out, there's plenty of more practical alternatives than using the OnStar antenna. I've been looking into getting a HAM license anyway for communications when storm spotting, so that's probably what I'll end up going with.
You can't go wrong in getting your HAM radio license... :smile:
 

WarGawd

Well-Known Member
#12
Kinda off your original topic but it seems safe to sidetrack this thread now since you mostly seem to have your question answered - I was just a little suprised that in this day and age of technology they still have people fulfilling that role. When I saw it in your sig, I googled it, and realized I was clearly deficient of any knowledge on the subject :biggrin:

Back in my youth in northern Manitoba and to a lesser extent in northern Alberta there used to be a whole pile of towers that were used for forest fire spotting. I always thought they had been abandoned for years because they were never manned and obviously lacking in upkeep whenever I climbed them. Just made me wonder if they still have people manning forestry towers anywhere.
 

Voymom

Well-Known Member
#13
I have my HAM License and it's the absolute best form of communication I have ever used. I too have my Technician's License but I have been studying to get my Extra. My dad travels a lot for his job, and I can talk to him and other people in different countries during contests, plus it is a major BONUS if your going to start spotting. I have been spotting since I was a child, and I have reported both using my HAM radio, and the cell phone, and HAM radio is so much easier lol.

Have you tried the online study test? I use that to help me study.

This is the site I use for the studying.

http://www.qrz.com/ht/?op=start&t=t2010
 

djthumper

Administrator
#14
Voymom said:
I have my HAM License and it's the absolute best form of communication I have ever used. I too have my Technician's License but I have been studying to get my Extra.

This is the site I use for the studying.

Practice Amateur Radio Exams by QRZ.COM
You still need to get General as well... :wink:

My 13 y/o just got his license at the beginning of September after going through a 3-day course that I was helping teach for my SaR team. Now my 6 y/o is studying on QRZ so he can get his license too. I need to get off of my butt and study for General, a test is next week...
 
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cody_s

cody_s

Well-Known Member
#15
I've been reading through some powerpoint I got of the Internet somewhere a while back. I'll have to check out that QRZ link, thanks for sharing VoyMom. WarGawd, yeah, we still have storm spotters :smile: While there have been advances in technology, you can see much more on the ground looking at a storm than you can when looking at a radar. Plus there's a certain adrenalin rush to watching a large storm come over. Not sure about Forest towers, but I wouldn't be surprised if those still get use too.
 

Voymom

Well-Known Member
#16
djthumper said:
You still need to get General as well... :wink:

My 13 y/o just got his license at the beginning of September after going through a 3-day course that I was helping teach for my SaR team. Now my 6 y/o is studying on QRZ so he can get his license too. I need to get off of my butt and study for General, a test is next week...
From what I understood and correct me if I am wrong, but you can skip levels? I think I'm wrong on this however...but I would still like to just skip general and get my extra lol. I THINK my dad said either my stepmom took all 3 and passed with her extra license or she skipped tech, gen, and went right into the extra and passed. I can't remember correctly. I am still studying all 3, and try to take in all the info I can.

cody_s said:
I've been reading through some powerpoint I got of the Internet somewhere a while back. I'll have to check out that QRZ link, thanks for sharing VoyMom. WarGawd, yeah, we still have storm spotters :smile: While there have been advances in technology, you can see much more on the ground looking at a storm than you can when looking at a radar. Plus there's a certain adrenalin rush to watching a large storm come over. Not sure about Forest towers, but I wouldn't be surprised if those still get use too.
Your welcome cody! It's a wonderful practice test! They update it with new questions with the actual questions that are on the tests so it helps you be better prepared. The testing is the easy part, learning the lingo, and etiquette are the hard parts :biggrin:
 
#17
I know this is a year-old thread and it got WAY off topic, BUUUTT.....

I am about to move to Detroit http://gmtnation.com/images/smilies/confused.gif, so I am installing a GPS that uses a prepaid GSM SIM card to communicate with a cell phone to gat long./latt. coordinates as well as a Google map link. It even has a relay to connect so I can interrupt my fuel pump remotely, get out my old combat gear, an' a-huntin' I will go http://gmtnation.com/images/smilies/biggrin.gif

This brings me to my point. Instead of using the GSM antennae that came with the thing, can I use the OnStar antennae? The device used a coaxial connection, below is an Amazon link so maybe someone could get a better look.

Amazon.com: Vehicle Car GPS Tracker 103B with Remote Control GSM Alarm SD Card Slot Anti-theft: Everything Else
 

RayVoy

Well-Known Member
#18
05Rainier said:
This brings me to my point. Instead of using the GSM antennae that came with the thing, can I use the OnStar antennae?
It will probably connect, but it may not work as well as the supplier antenna. Onstar went with the CDMA carriers, your GSM system uses different frequencies than the CDMA systems. The truck's Onstar antenna may not be tuned to the frequencies that your system requires.
 

DJones

Well-Known Member
#19
The antenna should be fine on both systems, but there is plenty of signal loss going through the glass. If you have the glass antenna.
 

RayVoy

Well-Known Member
#20
DJones said:
The antenna should be fine on both systems, but there is plenty of signal loss going through the glass. If you have the glass antenna.
The '05 should have the roof mounted "shark fin".
 

paul2005tb

Silver Supporter
#21
I can definitely understand the OP interest. If you park your car in locations with allot of kids around you run the risk of having a magnetic GPS / XM or cellular antenna ripped off. Not so with the OnStar shark fin antenna.
 

Reprise

Lifetime VIP Supporter
#22
Umm...this thread is a bit old :diggrave:
(but it brought back memories of CDMA & the beginnings of LTE)

More than that, though - it brought back memories of @The_Roadie, @Voymom , etc.
 

paul2005tb

Silver Supporter
#23
Please let me ask another set of related questions, 1) can the OnStar antenna be used as a gps antenna. There are two connectors coming from the OnStar antenna, one is green and the other is purple. If these can not be used then 2) the OnStar antenna roof hole seems to be a great port for the gps and or XM antenna in order to locate them on the roof. There are a few ways to get a clean installation of an antenna onto the roof but none better than the onstar factory port hole.

Right now I'm tempted to put that roof hole to use for the gps antenna and/or the SiriusXM antenna.
 
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#24
Apparently the trick is to find one of these 3 wired shark fins. When I was into Sirius XM, I actively looked for one and they were either hard to find or very expensive because of that rarity. The 2 wired ones are common. Don't know which wire does what but you could try doing a trace by unplugging at the OnStar module and putting a 9V battery to it and check for voltage at the antenna end. Or the schematics would say what colour does what.

I gave up Sirius a long time ago, now using Spotify on my Android HU.
 

paul2005tb

Silver Supporter
#25
Ok, not wanting to spend 100$ on another sharkfin dual or triple channel antenna, this morning I took a piece of 1/8in rubber mat and fashioned a "gasket" to my existing shark fin so that now the HU supplied gps antenna can fit tightly under it and snake to the roof porthole.

Attached are pictures.

It will be water tight after some black silicone sealant is applied liberally when I torque it down this weekend. That little dug out channel was done with a fine bit dremel tool, it will be how the aftermarket gps antenna cable runs behind the OEM onstar fin.


You can see that I took the dremel to the metal nut too so as to give me a bit more room for the 3 cables on that side.
 

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