Marahall gps system issue

[jaredharris]

Not sure if I am doing something wrong but when I turn my transmitter and receiver on and go to my app. The app arrow points in the wrong direction in which the transmitter actually is. I've been digging through the literature and not sure if their is a compass calibration of some sort but anyone with this system that could give me some help would be great!

I love the layout and everything just need to get this thing working!

[rkumetz]

Not sure if I am doing something wrong but when I turn my transmitter and receiver on and go to my app. The app arrow points in the wrong direction in which the transmitter actually is. I've been digging through the literature and not sure if their is a compass calibration of some sort but anyone with this system that could give me some help would be great!

I love the layout and everything just need to get this thing working!
What does the screen show for the position of the phone/tablet and for the transmitter? Are you by any chance indoors?

[citabria]

I've had this happen only when the transmitter was not connected to satellites

[jaredharris]

Me and my sponsor were playing with it in his backyard and absolutely nothing blocking the signal to the sky. I believe it showed me the one holding the iPad in his neighbors backyard and him with my red tail in a completely different direction then he was standing. The only thing I could come up with is maybe the compass is off? I've never had it show the blue dot and the red dot next to each other they are always complety apart by like 25 yards even though the receiver and transmitted are directly next to one another....

I've got to be doing something wrong... But I have no clue what

[Beaner]

I've never had it show the blue dot and the red dot next to each other they are always complety apart by like 25 yards even though the receiver and transmitted are directly next to one another....

I've got to be doing something wrong... But I have no clue what

Your not doing anything wrong its just the resolution of GPS
"Positional accuracy with a single receiver, to civilian users approximately equals 5m to 10m, 95% of the time, and the height accuracy is generally 15m to 20m 95% of the time. Military users receive a more accurate coded signal from the satellites."

[Icantmove]

Try it like 50ft or 100ft apart. My experience with my sponsor's setup is it basically doesn't work under 25ft or so; it'll do stupid things like tell you your tx is 60ft on your left when it's on your bird on your fist. Distance between the iPad / pocket link and the tx seems to fix that problem; the only time I've seen it wrong at distance is when the bird hit a fence and tore the tx off its leg (no significant injuries), and then it wasn't so much wrong as much as my sponsor just didn't look up to see the bird wasn't where the iPad said it was.

Also, you're the guy I talked to about the test in Lubbock, right?

[jaredharris]

Try it like 50ft or 100ft apart. My experience with my sponsor's setup is it basically doesn't work under 25ft or so; it'll do stupid things like tell you your tx is 60ft on your left when it's on your bird on your fist. Distance between the iPad / pocket link and the tx seems to fix that problem; the only time I've seen it wrong at distance is when the bird hit a fence and tore the tx off its leg (no significant injuries), and then it wasn't so much wrong as much as my sponsor just didn't look up to see the bird wasn't where the iPad said it was.

Also, you're the guy I talked to about the test in Lubbock, right?


This solved it just a little to close but solves the problem when farther away.

Yes sir! Glad to say I passed

[rkumetz]

This solved it just a little to close but solves the problem when farther away.

Yes sir! Glad to say I passed

Jared,
Keep in mind that the GPS doesn't get a position like "you are here at x y"
from the satellites. It uses the signal from a number of satellites to mathematically determine where it is on earth with respect to those satellites in orbit. If you have 2 receivers very close the error between the calculations done by the two receivers can be large enough that they appear to do unpredictable things relative to each other even though the actual error in absolute location is pretty good.

[jaredharris]

Jared,
Keep in mind that the GPS doesn't get a position like "you are here at x y"
from the satellites. It uses the signal from a number of satellites to mathematically determine where it is on earth with respect to those satellites in orbit. If you have 2 receivers very close the error between the calculations done by the two receivers can be large enough that they appear to do unpredictable things relative to each other even though the actual error in absolute location is pretty good.


Thank you for this! I understand how this thing actually works now. Makes complete sense when you explain it.... Im not really sure how I thought it worked but I was off. Needless to say we went hunting today and it performed great! Really a cool little tool

[Captain Gizmo]

In the basic form GPS is a +- 30 Meter accuracy system. If you are set up for WAAS (Wide Area Augmentation Service) you get down to the +-3 meter accuracy needed for a legal instrument aircraft approach. For the inch type accuracies needed for survey work you need a local augmentation system, usually a base station set up at the local section corner marker with a data link to the survey set, and then let it grind out an average for a while.

I would be surprised if Marshall comes up with a way to add WAAS to the transmitter (the Pocket Link maybe). I worked in this field. As it is I am very impressed by a GPS receiver, a data link transmitter, a command link receiver, and a beacon transmitter all crammed into 8.5 grams.

[Megapode]

Can we assume you have checked the location of your iPad? The transmitter may be fine but your tablet could be off giving you wacky results.
For instance, instead of the Marshall app, open the regular map app and hit the blue arrow in the corner. If the blue dot snapped to your current location right away you should be ok. If not it could be the iPad gps?

[rkumetz]

Can we assume you have checked the location of your iPad? The transmitter may be fine but your tablet could be off giving you wacky results.
For instance, instead of the Marshall app, open the regular map app and hit the blue arrow in the corner. If the blue dot snapped to your current location right away you should be ok. If not it could be the iPad gps?

The problem was that the TX and tablet/phone were closer together than the accuracy of GPS .