Sensing the World Around You
To collect data about the radio frequencies in these activities you need an RTL-SDR dongle like the one shown to the right. The buttons below provide some basic information to get you started. Then when you are ready start participating in the three activities described on this page. Do you have an idea for an additional activity? Scroll to the bottom of the page for an opportunity to in influence the future of this project.
This button will take you to an overview of the Electromagnetic spectrum.
This button will take you to a list of the required hardware and software.
This button will take you to a guide for setting up your RTL-SDR.
Activity One: Identifying Local Broadcasters
This activity will allow you to determine who is broadcasting in your local area. To get started make sure you have followed the instructions for setting up your RTL-SDR. Follow the instructions in the Scanning guide to install the correct software. Then get your equipment out and
start scanning the spectrum in your area. The broadcasters can change depending upon your
location, the time of day, and even the season. So scan, scan, scan to see who is broadcasting in
Be sure to upload your data when you are finished
scanning. No identifying information, beyond a zip code, is required. We just
want to get an idea of how many people are using the spectrum. You are welcome
to upload your data as frequently as once per hour. This information will be used to populate the Leader Board on the first day of each month.
Activity Two: Tracking Aircraft
This activity will allow you to detect the signals from
aircraft that are traveling in your area. Your dongle can detect the signals
from a plane’s automatic dependent surveillance-broadcast (ADS-B) transponder.
This is the same signal used by air traffic controllers to locate planes. You
will learn much more than just the location of the aircraft. Through the
software you will also learn the type of aircraft that is traveling overhead. In
addition, you will know where it took off and where it will land allowing you
to determine the flight paths that go over your area.
To get started make sure you have followed the instructions in the set-up guide at the top of this page. Next follow the instructions in the Tracking Aircraft Guide to install the necessary software. Finally, start scanning your skies to see what kind of
aircraft are flying overhead. Please remember to upload your data.
This information will help us determine how many planes are using the radio
frequencies at a given time. You may upload data as frequently as once per
hour. This information will be used to populate the Leader Board on the first day of each month.
Extension Activity: Receiving Satellite Signals
This activity is probably going to require a better antenna
than the one included with your RTL-SDR dongle. If you live in very flat area
and you have fair weather you may be able to detect a satellite with the
monopole antenna if you hold the it horizontally. However, it is likely you
will have to construct a special antenna in order to receive a signal from a
satellite. Get started by looking in the Receiving Satellite Signals guide.
There you will learn how to build a simple dipole antenna. If you would like to
make something more sophisticated there are a variety of other antennas you can
build to detect satellites. Simply Google RTL-SDR antennas for receiving
satellite signals and you will find many web pages with directions. Once you
have constructed a new antenna or have decided to give the monopole antenna a
try be sure to follow the instructions in the guide in order to download and
install the appropriate software.
Once you start scanning for satellites don’t forget to
upload your data.
We are interested in which satellites you are able to detect. You may upload
data as frequently as once per hour. This board will be determined by the number of times an individual uploaded
data about receiving satellite signals. This information will be used to populate the Leader Board on the first day of each month.
This is a citizen science project. Citizens are responsible for collecting the data, but they are also responsible for determining how the project expands. This project uses an RTL-SDR dongle to receive radio frequencies. The activity guide contains a couple of ways to use this device, but there are many more. If you enjoy using the dongle, explore what else you can do with it. If you find an activity that you enjoy and fits the parameters of this project, please fill out the form below. Your activity may be in the next edition of the activity guide.