How to Achieve the Best Possible Accuracy
Owner's manual. GPS systems
How to get the best GPS accuracy
Some things that move a GPS position are outside your control. The start sequence and the mode you choose are in your control. Do them the same way every day you fly.
5 quiet minutesHigh definition or EconomyTrackPack
Getting started
What changes the position
Mode. High definition is more accurate than Economy. This is the largest choice you control. The screen may show the letters HD or ECO.
Mount. Back, tail, leg, or neck. Higher and clearer is better.
Time since the first lock. How long the GPS has been running that day.
Sky. Cloud, leaves, or a roof overhead. Buildings and hills around you.
Satellites that day. How many are in view, and where they sit.
Your latitude. Closer to the equator, the satellites spread out more.
What the bird is doing. Flying is better than sitting in a tree or on the glove. The air is better than the ground.
The phone or tablet. Its own location has to be accurate.
Before you fly
Give the transmitter the best first lock, every day.
Start AeroVision7.
Turn on the PocketLink and wait until its light flashes white slowly.
Go outside, with a clear view of the sky, and install the battery.
Set the transmitter on something that does not move, with open sky above it. Let it find the satellites, then leave it there for 5 minutes so every satellite in view is locked.
After those 5 minutes, put the transmitter on the bird and fly.
If you must hold the transmitter, hold only the body, with the antenna pointing away from you. Do not start it in a car or a building. Do not hold the antenna while it is searching. That lowers GPS sensitivity.
How the transmitter sits on the bird
Use the mount that matches the hardware on your transmitter. These photos are from the Marshall site.
Choose a mode
High definition
The most accurate mode. The screen may show the letters HD. Use it for a drone flight or when you want a precise record. It makes a clean track for 3D replay.
Economy
About half the power. The screen may show the letters ECO. It trades some accuracy for a longer run. Use it for hunting and recovery, when battery life matters more than exact speed and height.
Set the phone or tablet to Always Allow
AeroVision7 uses the device location for your position (the red dot), the heading toward the bird, and pitch when altitude is set to Above Me. The default permission, While Using the App, turns the phone location off as soon as the app goes to the background or the screen locks. After you come back, every number that uses your location can be wrong for several minutes.
Open the device Settings.
Scroll to AeroVision7 and tap it.
Set Location to Always Allow.
Turn Precise Location on.
With those set, AeroVision7 keeps an accurate position while it is connected to a PocketLink, even in the background. Heading and distance depend on that position.
Altitude: Above Start or Above Me
Above Start
The more accurate reading during a flight. It uses only the GPS inside the transmitter. Choose it when you want the best altitude.
Above Me
Useful if you drive or change height during a flight. It is a live difference against the phone. It is always less accurate than Above Start.
Troubleshooting
Work down this list. Stop when the positions look steady.
The track jumps or the height looks wrong. Take the battery out and start again outside. Set the transmitter on something that does not move, with the antenna pointing away from you. Wait 5 minutes before you put it on the bird.
You started it in a car, in a building, or while holding the antenna. Take the battery out. Start again under open sky. Do not hold the antenna while it searches.
The numbers look wrong after the phone was locked. Set Location to Always Allow and turn Precise Location on. While Using the App turns the phone location off in the background.
Altitude looks off while you drive. Use Above Start. Above Me follows the phone and is less accurate.
The fix is weak when the bird is on the ground. A leg mount is shaded on the ground. A TrackPack keeps the antenna clear.
FAQs
What changes a GPS position the most?
The mode. High definition is more accurate than Economy. The screen may show the letters HD or ECO. The mount, the sky, the satellites that day, and what the bird is doing also move the position.
How long should I wait before I fly?
Set the transmitter outside on something that does not move, with open sky above it. After it finds the satellites, leave it there for 5 minutes. Then put it on the bird.
Which mode should I use?
High definition for a drone flight or a precise record. Economy for hunting and recovery, when battery life matters more than exact speed and height.
Why do the numbers look wrong after the phone was locked?
Set Location to Always Allow and turn Precise Location on. While Using the App turns the phone location off in the background.
Should I use Above Start or Above Me?
Above Start is the more accurate reading during a flight. It uses only the GPS inside the transmitter. Above Me follows the phone and is less accurate.
