Moderated Discussion Areas
  ContinuousWave: Small Boat Electrical
  GARMIN Buyer Confused About Need for GPS Antenna, XM Chip

Post New Topic  Post Reply
search | FAQ | profile | register | author help

Author Topic:   GARMIN Buyer Confused About Need for GPS Antenna, XM Chip
fishyman666 posted 05-09-2008 04:49 PM ET (US)   Profile for fishyman666   Send Email to fishyman666  
Hello all, I just bought a GARMIN 540 yesterday. I am confused as to [whether] or not [I] need a $60 external antenna. My current [GPSr] is mounted on the dash with bracket and antenna. I have a hard top. I am also considering buying the XM wire for the RADAR and XM radio.I don't understand how the radio will work. I can't believe that [I] also need to buy a chip to get the included features. I am confused and could sure use some advice.Thanx...Pete
ConB posted 05-09-2008 05:42 PM ET (US)     Profile for ConB  Send Email to ConB     
Your 540 has an internal antenna. It may or may not work under a hard top. Try it and see. An external antenna can be added if need be.

The XM radio weather is a different antenna, 31 Smart antenna I think. Then you need to subscribe to the XM weather and audio.

The 540 has very good chart coverage. It doesn't have inland lakes though. You can also buy a G2 chip that gives more detailed views on places.

Do a search on this site for articles by Bluewaterpirate, he is an expert.


seabob4 posted 05-09-2008 05:58 PM ET (US)     Profile for seabob4  Send Email to seabob4     
Unfortunately, to get XM weather (and XM radio), you have to get the GDL30A XM receiver. Our cost is $560. Right now, Garmin and Raymarine are the only ones offering XM weather. Do yourself a favor, enjoy the display, which is excellent, and stick to the NOAA reports on your VHF. And pay attention to your surroundings! There's your weather report.
ConB posted 05-09-2008 06:46 PM ET (US)     Profile for ConB  Send Email to ConB     
When all else fails, read the manual. GXM 31 Smart antennas are for sale lots of places for $220.00.


seabob4 posted 05-09-2008 07:12 PM ET (US)     Profile for seabob4  Send Email to seabob4     
Old stuff. NMEA 0183. Sorry. Dealing in NMEA 2000. My apologies.
jimh posted 05-09-2008 09:21 PM ET (US)     Profile for jimh  Send Email to jimh     
I am surprised that GARMIN does not provide literature in the box that comes with their unit that makes clear the need for an external antenna. Usually electronic devices come with some literature that explains how to connect them and use them.
seabob4 posted 05-09-2008 10:03 PM ET (US)     Profile for seabob4  Send Email to seabob4     
Try interfacing a Garmin 5212 with GDL30 XM weather and a Sony head unit, XM stereo upgrade! Long hours on the phone with some geek in India! Doable, but with effort. And do you know what is the kicker? BRP and Suzuki's Networks are all NMEA 2000. BUT, Garmin's GPS antenna is still 0183! Do they bother to tell anybody that? NOOOOOOO!!!! So if you have I-Command or Suzuki's, combined with Garmin, you have to have 2 GPS beacons. Thanks a lot!
bluewaterpirate posted 05-10-2008 12:14 AM ET (US)     Profile for bluewaterpirate  Send Email to bluewaterpirate     
SeaBob .....

1. Garmin is the only vendor that offers XM weather & music functionality. Raymarine, Furuno, and Northstar offer Sirius weather & music functionality.

2. There is no NMEA 2000 connectivity in the Garmin 400/500 series chartplotters only NMEA 0183. The GXM 31 Smart Antenna connects to the chartplotter via a mini usb connector and rca connector to the aux channel of your radio. 16215539/file.jpg 16215542/file.jpg

3. Yes the GPS 17 antenna is connected via NMEA 0183, however, the 5212 is now shipping with the new GPS17x NMEA 2000 antenna and a full NMEA 2000 backbone. In as much as yours didn't come with this antenna you can purchase the GPS 17x NMEA 2000 antenna seperately.

4. I'm not sure what your trying to connect to your GDL30A but there is no NMEA 0183 connections available from that unit. The GL 31 antenna connects to the unit via a BNC connector and there is an audio cable that has two rca jacks that connect to the aux channel of your radio. There is no need to buy an XM ready radio. The 5212 controls all the XM music functionality (channel selection) and passes to your radio via the rca jacks.

5. Software update 3.00 for your 5212 added support for new categories of NMEA2000 data, including Navigation, GPS, Fuel, Depth, Water Speed, and Temperature so you can connect to the rude and zuke motors.

5. If you would have gone to the Garmin site a read all the material available you would have saved yourself the apparent heartburn.

Here's what now ahipping the 5212 box.

GPS 17x antenna
Protective front cover
Top & bottom snap covers
Video cable assembly
Power cable assembly
NMEA 0183 cable
NMEA 2000 drop cable
NMEA 2000 power cable
NMEA 2000 T-connector & terminator kit
Flush mount hardware
Flush mount gasket
Marine grommet kit
Manual case with owner's manual
Quick reference guide
Installation instructions


jimh posted 05-10-2008 08:52 AM ET (US)     Profile for jimh  Send Email to jimh     
This might be worthy of its own discussion, but perhaps I can raise this question here: Will the recent merger between XM and Sirius affect existing devices which are using their services?
bluewaterpirate posted 05-10-2008 09:13 AM ET (US)     Profile for bluewaterpirate  Send Email to bluewaterpirate     

That's yet to be seen. I've seen nothing in writing that would indicate what will happen. XM/Sirius different providers for the weather side plus I'm not sure of market size (i.e. how many boaters actually subscribe to the service). XM is ahead of Sirius when it comes to weather functionality and display.

I know from experience it saved me a number of times fishing offshore.


seabob4 posted 05-10-2008 03:00 PM ET (US)     Profile for seabob4  Send Email to seabob4     
Thanks for the info. We use Garmin as our factory supplied electronics manufacturer, and fortunately we don't many Stereo XM upgrades along with the XM weather option. The last one I did, Garmin hadn't upgraded the GPS17 to NMEA 2000 yet. That is good to know, although it would have been even nicer if Garmin contacted us to let us know!

I am not an electronics expert, although I do have a bit of knowledge. Maybe dangerous, some say! But you my friend, you seem to have an excellent handle on the state of the electronics industry. I shall pay attention from now on. Our biggest gripe with Garmin is that if we have an Evinrude I-Command or Suzuki Digital Gauge Install, we had to mount 2 GPS antennas because Garmins was 0183 and Evinrude/Suzuki are 2000. Trust me, I will be calling Garmin Monday morning to give them a ration of you know what.

Thanks for putting me in my place. Sometimes I need that!

BellBoyBob posted 05-13-2008 11:45 AM ET (US)     Profile for BellBoyBob  Send Email to BellBoyBob     
I have the Garmin 540s and when I power on, I can aquire satellites through the garage roof. It is equipped with the internal antenna. I cannot imagine there being a problem under a bimini (canvas) or hard top out on the water. The XM antenna is needed for XM reception plus the subscription. As it has been stated here, the weather alerts and general info can be received through a VHF radio making the XM weather redundant. HOWEVER, the XM surface radar option is nice as it can be displayed on your 540's screen alerting you to exactly where the dangerous cells are vis-a-vis your boat position.


Post New Topic  Post Reply
Hop to:

Contact Us | RETURN to ContinuousWave Top Page

Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.