EchoHunt: test your signal with public SDRs (radio amateurs & DXers)





What is EchoHunt and why is it different?

EchoHunt is a web tool built for radio amateurs and DXers who want to stop “imagining” propagation and start listening to it. Instead of showing theoretical maps or prediction models, EchoHunt uses public SDR receivers (KiwiSDR) distributed around the world to record short audio fragments of your transmission and return them as an echo.

This way you can check in real time how your signal travels across the planet, which receivers attempted to catch your transmission, and how your audio sounds on the other side. Perfect for testing antennas, gear, power, audio, and propagation conditions without installing software or relying on third parties.

Real audio, not simulations

EchoHunt works with real signals captured by public SDRs. What you hear is exactly what reached those receivers during your transmission.

Compatible with any radio setup

It works with CB, HF, and related bands, in AM, FM, USB, or LSB. You only need your radio, a frequency, and the desire to test.

Everything from your browser

No installation, no registration, and no weird configurations. Open EchoHunt, enter the frequency, transmit, and listen to your echo.

How EchoHunt works (Quick Hunt, Deep Hunt)

Using EchoHunt is simple, but very powerful. You only need your radio gear and follow these steps:

  1. Enter the frequency in MHz you want to test. Type it with a decimal point, for example: 27.555.
  2. Choose the transmission mode: AM, FM, USB, or LSB, depending on your equipment and the band you’re using.
  3. Select the hunt type:
    • Quick hunt: checks fewer SDRs to give you an almost immediate result.
    • Deep hunt: scans a larger number of public SDRs for a more complete propagation analysis.
  4. Start transmitting from your radio and hold the PTT for a few seconds.
  5. Click “Start Echo” only once and wait for the list of audio recordings captured by the SDR receivers that attempted to catch your signal.

In a few seconds you will have real recordings of your signal, captured from different KiwiSDR receivers around the world. You’ll be able to hear your own audio “from the outside” and see on the map which SDRs participated in the hunt, allowing you to check live whether propagation is useful and how far your transmission can reach.

Who is EchoHunt useful for?

EchoHunt is designed for anyone who enjoys the world of radio, from the DX radio amateur to the shortwave listener:

  • DX-focused radio amateurs: check in real time how far your signal can go by testing different antennas, power levels, equipment, and schedules.
  • International broadcast listeners: find which public SDR is best suited to listen to a specific shortwave station.
  • Experimenters and curious minds: if you’re interested in radio-wave propagation, EchoHunt gives you a practical and visual way to understand how signals travel globally.

Whether you’ve been chasing DX for years or you just discovered shortwave listening, EchoHunt turns propagation into something you see and hear, not just numbers or theories.

Try it, experiment, and share it

The best way to understand EchoHunt is to use it: enter a frequency, transmit for a few seconds, and listen to how your signal reaches (or doesn’t reach) different SDR receivers around the world. Play with bands, modes, and schedules to see how propagation changes in each situation.

If EchoHunt is useful to you, you can share it with your radio friends, DX groups, and the usual forums. The more people use it, the more sense it makes to keep developing and improving the tool.

EchoHunt updates

EchoHunt is under active development. All improvements, fixes, and new features are collected on a dedicated release notes page. If you want to see what has changed, what has been optimized, or what is being tested, you can check the full history here: view EchoHunt updates .

Scroll to Top