A Radio Microphone System was required for some video work. The receiver was developed using the CA3189 device. Its IF and detection are at 10.7MHz and the local oscillator is crystal controlled for stability. The frequency of operation is 174MHz which is a standard Radio Microphone channel. The transmitter uses a crystal controlled oscillator running at 14.5MHz, this oscillator is frequency modulated using a varicap diode. The 14.5 MHz is multiplied up in three stages (*3,*2 and *2) to 174MHz.