Decoding

Blue Box can decode DTMF combinations using the microphone on the device.

Note: In order for this feature to work, you must agree to allow the app to access the microphone on the device. No audio is recorded, stored or shared. The audio stream is used only for decoding DTMF combinations.
If a prompt does not appear asking to use the microphone, check Device Settings>Blue Box and enable the Microphone setting.

Decode Tones

  1. Press the Mode button to toggle between encoding Encoder and decoding Decoder modes.
  2. Reduce ambient noise as much as possible.
  3. Play the device near the source of DTMF signals.
  4. Adjust the distance to the source as needed to achieve best results.
  5. Adjust the Power Measurement and Noise Level settings as needed to achieve best results.
  6. Press the Mode button again to stop decoding. Or press any tone generating button.