Stereo Encoder Mmc4066e Mmc4047
To adjust the frequency rotate R13 (multiturn) untill on IC2 pin 10 you measure 19kHz or the stereo led lights up on your stereo receiver. From R10 adjust the pilot tone signal and from R7 adjust the sound level. Use metallic resistors and 100nF ceramic capacitor for low noise stereo signal.If your audio source has dc voltage on audio output connect 2 x 0.47uF capacitor on the stereo encoder inputs. You can use a better T1 like BC549C if you want a higher sound amplification. Simply select transmission frequency at which you would like to transmit, set the combination for 4-DIP switch and BH1417 will tune to that frequency.
Stereo Encoder Mmc4066e Mmc4047 Video
If you can’t hear the transmitted audio signal on your FM receiver then re-adjust 2.5 turn variable coil until you can hear the signal.Technical Specifications:Supply Voltage: 4 – 6VTransmission Frequency: 87.7 – 88.9MHz, 106.7 – 107.9MHz (200kHz steps)Output RF Power: 20mWAudio Frequency: 20 – 15KHzSeparation: 40dBPower Consumption: 30mAComponents:1x BH1417 – Stereo PLL Transmitter IC (Case SOP22)1x 7.68 MHz Crystal1x MPSA13 – NPN Darlington Transistor1x 2.5 Turns Variable Coil1x MV2109 – Varicap Diode1x 4-DIP SwitchANT – 30 cm of copper wire.