NodeMCU + I2C-controlled FM Transmitter + AP Mode + TRS Electret Microphone
= Remote Control Listening Device

Adafruit Stereo FM Transmitter with RDS/RBDS Breakout – Si4713

  1. Solder length of wire for antenna
  2. Wire up Si4713 breakout board to NodeMCU

Node Si4713 3V -> VIN GND -> GND D1 -> SDA D2 -> SCL

  1. Connect TRS electret mic to Si4714 TRS jack
  2. Upload firmware
  3. Connect to “hackerradio” AP broadcast by NodeMCU
  4. Open browser, navigate to
  5. Enter a frequency and click submit (For example 102.35MHz should be entered as 10235)
  6. Tune FM radio to same frequency
  7. Talk and listen