Frequently Asked Questions
Whats the backstory to this project?
The project began in 2012 at Arizona State University as a student powered instrumentation development. It has been supported by the National Science Foundation (AST-1407646, AST-1711179)
Do you buy drones or build your own?
We have used both Commercial drones and custom builds. The current Mark 7 platform (ca 2019) is a custom build using kit parts. (build log in memo 51)
What kind of antenna do you use
We use the Aaronia Bicolog 5070. It is a calibrated biconical rated from 30MHz to 2GHz. There are higher frequency models available. It is robust to abuse and has a very smooth frequency response.
How high do you fly?!
We are limited by FAA regulations to a height of 400ft above ground. Much higher and one loses line of sight anyway.
How long can the drone stay up?
Flight time: 45min hover, 30 minute mapping sorties
How do you mount everything?
This is the main question! We’re always making new mounts. They are generally 3D printed PLA and fixed beneath the drone between the legs.
Doesn’t the presence of the drone distort the calibrator beam?
Modeling suggests that proximity to the drone is not the dominant uncertainty in the drone beam.
Does the Mk7 battery really mount on top?
Yes. This is somewhat novel for a battery of the size we’re using, but despite seeming dreadfully unstable it works fine
What is the frequency Coverage?
We’ve tested with tones at 137Mhz and at 70MHz. Eventually our goal range is 50 to 250MHz with at least 20MHz simultaneous coverage.
What is the drone position accuracy?
We estimate 8cm uncertainty using RTK GPS. The actual positioning accuracy is less.
What transmitters do you use?
- Transmitter V1 used dual tone Valon 5009 VCO (23 - 6GHz).
- TX V2 will add chopping.
- TX V3 will add 20MHz band limited noise
Who does the flying?
Danny is Part 107 certified pilot with 7 years, 45 hours on controller with a 100+ flights.
What is in your field kit?
3 spare drones (essential!), 2 spare antennas, SAS542 folding bicone + stand for auxiliary receiver. The whole mess fits into 4 custom pelican cases.
How much does the drone build cost?
The Mk7 cost ~$1200 each in parts in 2018