E

eld

Active Member
I don't know why my GPS display "3D Differential" to "3D GPS Degraded" with a GA26X antenna.
I have not find this value ("3D GPS Degraded") on manual.

this transition to "3D GPS Degraded" is very frequent without me understanding why and without external change, without loss of statelite, when I have make this capture, I have not all satelite on vision (north), but it's the same problem when I receive all satelites.

Besides, the AERA 660 and 760 receive satellites better and without problems from the same place at the same moment.

20240609_224740.jpg20240609_224753.jpg
 
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Only a few hundred things could be going on here :) Here's a few that come to mind --

1. Antenna has or is failing
2. Antenna connector is bad/failing
3. Antenna coax is crimped, crushed, pinched
4. Something blocking the antenna's view of the sky
5. Excessive interference in the vicinity on L1,L3, L5 frequencies, OR other RF interference.
6. WAAS/SBAS GNS receiver in GDU is failing

Got any pictures of your antenna and coax installation?
 
bjdecker said:
Only a few hundred things could be going on here :) Here's a few that come to mind --

1. Antenna has or is failing
2. Antenna connector is bad/failing
3. Antenna coax is crimped, crushed, pinched
4. Something blocking the antenna's view of the sky
5. Excessive interference in the vicinity on L1,L3, L5 frequencies, OR other RF interference.
6. WAAS/SBAS GNS receiver in GDU is failing

Got any pictures of your antenna and coax installation?
Click to expand...
Antenna and G3X is not installed, it's new antenna and G3X, just tested on G3X, cable, connector are clean, we have tested at different location.
Why bar for each satelite have the same size and pass from green to grey ?
If there was excessive interference, the aera 660 and 760 would be impacted, this is not the case.
 
eld said:
Antenna and G3X is not installed, it's new antenna and G3X, just tested on G3X, cable, connector are clean, we have tested at different location.
Why bar for each satelite have the same size and pass from green to grey ?
If there was excessive interference, the aera 660 and 760 would be impacted, this is not the case.
Click to expand...
Whose antenna are you using and model? I've seen those who use the "less expensive" (Titan antenna, carried by Mouser, etc.) GPS antenna do this. Assuming you are observing the min amount of cable needed.
 
dmattmul said:
Whose antenna are you using and model? I've seen those who use the "less expensive" (Titan antenna, carried by Mouser, etc.) GPS antenna do this. Assuming you are observing the min amount of cable needed.
Click to expand...
a Garmin GA 26X antenna and GA 35.
 
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supik said:
I was thinking about GPS spoofing going on in Eastern EU because of the war, but that's apparently not your case..
Click to expand...
I don't think so either, the 660, 760 and 650xi work well at the same place.
 
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eld said:
I don't know why my GPS display "3D Differential" to "3D GPS Degraded" with a GA26X antenna.
I have not find this value ("3D GPS Degraded") on manual.

this transition to "3D GPS Degraded" is very frequent without me understanding why and without external change, without loss of statelite, when I have make this capture, I have not all satelite on vision (north), but it's the same problem when I receive all satelites.

Besides, the AERA 660 and 760 receive satellites better and without problems from the same place at the same moment.

View attachment 64395View attachment 64396
Click to expand...
The experimental antenna GA26X is intended for hand held and G3X avionics.
The GA35 antenna is an IFR approved WAAS antenna for certified GPS and it also works with the G3X system.
Note that G3X is also used under STC in certified aircraft.
I assume this has to do with legal issues.

Good luck
 
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Avanza said:
The experimental antenna GA26X is intended for hand held and G3X avionics.
The GA35 antenna is an IFR approved WAAS antenna for certified GPS and it also works with the G3X system.
I assume this has to do with legal issues.

Good luck
Click to expand...
I use GA35 to test if GA26X have issue, I have issue with both :-(
 
Avanza said:
The experimental antenna GA26X is intended for hand held and G3X avionics.
The GA35 antenna is an IFR approved WAAS antenna for certified GPS and it also works with the G3X system.
Note that G3X is also used under STC in certified aircraft.
I assume this has to do with legal issues.

Good luck
Click to expand...
Perhaps you should review the manual before making such statements?
The 26X is the approved antenna for use with GDU 37X, 4XX units.

20: GPS/XM ANTENNA INSTALLATION
NOTE
GA 35, GA 36 and GA 37 antennas cannot be used with GDU 37X/4XX units.
 
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Walt said:
Perhaps you should review the manual before making such statements?
The 26X is the approved antenna for use with GDU 37X, 4XX units.

20: GPS/XM ANTENNA INSTALLATION
NOTE
GA 35, GA 36 and GA 37 antennas cannot be used with GDU 37X/4XX units.
Click to expand...
Yes you are correct. my misstake, I have GPS 20A wich uses the GA35.
 
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