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Bought Garmin G5 (non cert) Question on GPS Input and GPS Antenna

jackking123

Well Known Member
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I bought a G5 Exp. This is going to be stand alone as a backup. I have the magnetometer. GPS is the question, either internal or external.

External GPS
I want to use my GRT Safe-Fly GPS (to provide GPS information to the G5 via the RS232. Will Garmin accept GPS position from non Garmin Product.

GRT GPS outputs available. RS232:
Serial Port Default Pins
Serial Port 1 Out 4800 baud, NMEA0183 19,20
Serial Port 2 Out 9600 baud, NMEA0183 + RAIM 3
Serial Port 3 Out 115200 baud, NMEA0183 + RAIM 1,2

Antenna
Garmin G5 has internal GPS and requires external antenna. I did not get an antenna. I don't want to add more antennas especially a $250 Garmin antenna. Question do these off the shelf $15 GPS with BNC connectors work?
 
Maybe?

You don’t need the antenna. The internal antenna worked fine in my RV-8 before I installed an antenna for WAAS. I got accurate GPS heading and ground speed using the internal G5 gps antenna.

Why do you need to feed it a GPS position if you already have the magnetometer? Unless you are looking for ground speed…or are you using it as an HSI?

Most cross brand compatibility goes through the ARINC 429 module Garmin sells (GAD29). I found the G5 serial data is of limited use. If you need to feed it navigation information for an HSI then you’ll need the GAD29.
 
I bought a G5 Exp. This is going to be stand alone as a backup. I have the magnetometer. GPS is the question, either internal or external.

External GPS
I want to use my GRT Safe-Fly GPS (to provide GPS information to the G5 via the RS232. Will Garmin accept GPS position from non Garmin Product.

GRT GPS outputs available. RS232:
Serial Port Default Pins
Serial Port 1 Out 4800 baud, NMEA0183 19,20
Serial Port 2 Out 9600 baud, NMEA0183 + RAIM 3
Serial Port 3 Out 115200 baud, NMEA0183 + RAIM 1,2

Antenna
Garmin G5 has internal GPS and requires external antenna. I did not get an antenna. I don't want to add more antennas especially a $250 Garmin antenna. Question do these off the shelf $15 GPS with BNC connectors work?
I just installed a G5 in my RV-8 and unlike Chris, my reception with the internal antenna was poor at best with frequent lost signals leading to lost track and ground speed indications. I contacted Dynon to see if the HDX could supply GPS information to the G5 via a serial output. Their answer was that the G5 is not compatible with Dynon at all so the only solution for me was an external antenna. I added an antenna that matched the Garmin frequency (1575.42 Mhz), gain (28 Db), voltage (3-5V) and supply current (10mA) and got it from Amazon for less than $10. It has an SMA connector so you'll need an adapter to connect the antenna to the G5.

The antenna is very small and I placed it on the glare shield. I did cut the cable to feed it to the back of the panel so I had to buy an RG174 crimper and the RG174 male crimp connectors. All of it was less than $35, including the new crimping tool. GPS reception is outstanding now. If you can crimp RG400 connectors, you can do the same with the RG174 cable, it's just a lot smaller so make sure you have a good magnifying glass so you don't have any errant wire strands. No dropped signals at all even during extensive aerobatics.
 
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My G5 gets its info from the navigator and displays track instead of course...no GPS required. I can switch to the internal GPS if necessary, but I've found that to be an unreliable signal and didn't want to spend the money ($250 IIRC) for an external antenna. I have no shortage of GPS redundancy. In my experience, the G5 needs a GPS antenna.
 
Great answers. I did some more reading and the G5 RS-232 serial can get GPS NEMA info (4800, 9600 baud), and the config page on unit has NEMA.
Is it compatible with the GRT GPS? Have to make some calls and try it. The GRT GPS spits out many NEMA sentences. I would not be surprised if Garmin was proprietary. Kind of expect it. The cheap antenna will work.

GRT Safe-Fly GPS
NMEA0183 Sentences Transmitted
$GPGGA"
$GPGLL
$GPGSA
$GPGSV
$GPRMC
$GPVTG
$GPZDA
$RAIM (proprietary)

[EDIT] I think I found the answer. "Garmin Proprietary NMEA 0183 Sentences TECHNICAL SPECIFICATIONS". Garmin has their own NMEA sentences it seems? Looks like I will get an antenna for the G5.
 
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