1. Transmitter module stereo transmitter IC, stereo transmission, can also input only mono 2. The transmission frequency covers China, Japan, Europe FM band, 76MHz to 108MHz adjustable, input coupling and signal coding, through the precision algorithm design, the sound is demodulated and played back, whether high or low, there is first-class performance, the sound quality is very Well, the distortion rate and signal-to-noise ratio have already met standard and have reached the broadcast standard. 3. Instructions: Short press the F+ button to search for the station upwards. After searching the station, it will stop and play the station. Press and hold the F+ button and the receiving frequency is incremented by 0.1MHz. Short press the F- button to search for the radio downwards. After searching the station, it will stop and play the station.Press and hold the F- button and the receiving frequency is decremented by 0.1MHz. 4. Short press the V+ button, the volume will increase by one level, and the maximum volume position is 8. Press and hold the V+ button to restore the factory default parameters, frequency 99MHz, volume level 6. Short press the V- button to decrease the volume by one level, the minimum level is 0 (mute). Press and hold the V- button to turn it off. After shut down, press any key to turn it on. 5. Without the button operation, the backlight will go out after . After three minutes, the LCD screen will go out and the peripheral circuits will go to sleep. After the light is off, press any key to wake up the relevant circuit, the light and the screen resume display. This time the button is non-functional, only the function, after the light is on, each button has the corresponding function. Condition: New Power Supply: DC 3V-12V Working Current: 22mA Shutdown Current: 30uASensitivity: 1.3uV Volume: 9 levels, level 0 , level 8 maximum sound Output: Directly drive universal earbuds. Frequency and volume have power-off memory function. In the off state, press any key to turn it on, long press V- button to shut down. Line O socket is an audio output, standard 3.5mm size, can directly drive the common 32 ohm earplugs. The ANT socket is for antenna connection. colour:Black Material:PCBA board + plastic + metal size:53mm x 31.7mm Package Contents: 1 x FM Receiver Board Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.