Category: Discovery Drive

WOW@Home: A Global Network of RTL-SDR Based Radio Telescopes Looking for Alien Technosignatures

The Wow! signal is a famous, strong, and unexplained radio signal detected in 1977 by the Big Ear radio telescope in Ohio, lasting 72 seconds and appearing to originate from the constellation Sagittarius. Its origin remains unknown, with some speculating that it could be an extraterrestrial technosignature. Upon reviewing the signal data, Astronomer Jerry R. Ehman discovered the powerful signal burst in the readout and wrote a large "Wow!" next to it, unintentionally coining the name.

Wow@Home is a new project that aims to coordinate a network of small radio telescopes globally, in the hopes of increasing our chances of detecting interesting astrophysical and technosignature events, such as the Wow! event.

A network of small radio telescopes offers several distinct advantages compared to large professional observatories. These systems are low-cost and can operate autonomously around the clock, making them ideal for continuous monitoring of transient events or long-duration signals that professional telescopes cannot commit to observing full-time.

Their geographic distribution enables global sky coverage and coordinated observations across different time zones, which is especially valuable for validating repeating or time-variable signals. Coincidence detection across multiple stations helps reject local radio frequency interference (RFI), increasing confidence in true astrophysical or technosignature transient events.

These networks are also highly scalable, resilient to single-point failures, and capable of rapid response to external alerts. Furthermore, they are cost-effective, engaging, and accessible, ideal for education, citizen science, and expanding participation in radio astronomy.

However, these systems also come with notable limitations when compared to professional telescopes. They have significantly lower sensitivity, limiting their ability to detect faint or distant sources. Their angular resolution is poor due to smaller dish sizes and wide beamwidths, making precise source localization difficult.

Calibration can be inconsistent across stations, and frequency stability or dynamic range may not match the performance of professional-grade equipment. Additionally, without standardized equipment and protocols, data quality and interoperability can vary across the network.

Despite these constraints, when thoughtfully coordinated, such networks can provide valuable complementary observations to professional facilities.

The team note that the Wow! signal was strong enough that it could have been detected by a small home radio telescope. They go on to make the case that we could be missing out on detecting many compelling signals simply because radio telescopes aren't watching every part of the sky simultaneously. 

The project will monitor the Hydrogen Line frequency for interesting signals. Currently, the team is using a WiFi grid dish and an external LNA as the radio telescope hardware, but they also aim to evaluate our Discovery Dish with H-Line feed.

Wow@Home Typical Radio Telescope Hardware
Wow@Home Typical Radio Telescope Hardware

Discovery Drive: An Affordable Antenna Rotator Crowd Funding Pre-Launch Page now Active!

We're happy to announce that the pre-launch page for our "Discovery Drive" automatic antenna rotator is now live! Please sign up to be notified of when the crowdfunding page goes live as the price will be reduced by at least $100 during the campaign.

Discovery Drive is an automatic antenna rotator that is designed to be used with our Discovery Dish product, as well as similarly sized antennas such as Wi-Fi grid and Yagi antennas.

Discovery Drive with Discovery Dish Mounted
Discovery Drive with Discovery Dish Mounted

A motorized rotator allows you to use a satellite dish or directional antenna to track and receive signals from polar orbiting satellites, which quickly move across the sky. It also lets you switch swiftly between geostationary satellites without manually realigning the dish. 

Examples of polar-orbiting weather satellites that you can track include NOAA POES, METEOR-M2, METOP, and FENGYUN. Depending on your location, you may also have access to other interesting satellites that dump data over specific regions. Amateur radio operators can also use Discovery Drive to track amateur radio satellites with Yagi antennas.

Discovery Drive
Discovery Drive

Discovery Dish is designed to be easy to set up and use. Unlike many other rotators on the market, no external controllers are required. Discovery Drive has a built-in ESP32 controller, and control can be commanded over WiFi or serial from rotctl-compatible software such as SatDump, GPredict, and Look4Sat on Android. 

Features and Specifications

  • Up to 125 kgcm (12.25 Nm) of torque
  • ESP32 control board
  • ± 1.5° of accuracy
  • -360° to +360° Azimuth range, 0° - 90° elevation range
  • 1.5 RPM Azimuth speed, 0.25 RPM elevation speed
  • 12 V power input (either barrel jack or USB Type-C Power Delivery)
  • Wi-Fi connectivity with browser-based web UI
  • Serial over USB data connectivity or Wi-Fi data connectivity
  • Low power draw (< 10 W, can be powered with PoE+ supplies and still have power left over for powering a single board computer and RTL-SDR)
  • Robust worm gear-locked output drives
  • Direct rotctl compatibility over Wi-Fi (compatible with programs that implement the rotctl protocol, such as SatDump, GPredict, and Look4Sat on Android)
  • Hamlib compatibility (EasyComm II protocol)
  • Waterproof outdoor enclosure
  • Open source ESP32 firmware 
Discovery Drive Inside Look
Discovery Drive Inside Look