DUPLEX OPERATING CURVES
The curves indicate the amount of attenuation (isolation) required between a "typical" transmitter (50 watt) and receiver to prevent greater than 1 dB reduction in a 12 dB SINAD ratio, due to (1) transmitter noise and (2) receiver desensitization. As an example, a 150 MHz duplex station – would require approximately 51 dB attenuation of transmitter noise at the receive frequency, and approximately 48 dB receiver desensitization isolation (receiver isolation from the transmitter carrier frequency).
CAUTION: These curves are typical curves and should not be used when accuracy is desired. They are meant to serve only as a guide. For exact requirements of a specific duplex station, contact the manufacturer of the radio equipment.