WIRELESS IR HEADPHONE TRANSMITTER

WIRELESS IR HEADPHONE TRANSMITTER

 The transmitter for the wireless headphones is built around a CD4046 CMOS phase-locked loop, coupled with a driver transistor, and a pair of infrared LEDs.
Although the CD4046 is comprised of two phase comparators, a voltage-controlled oscillator (or VCO), a source follower, and a zener reference, only its VCO is used in this application.

click to enlarge circuit