The Model FT-1 is a Radio Interference Field Tester is designed for testing the RF environment around 318 MHz. It will decode any Megacode formatted RF data transmission and then give a short Beep signal from the loudspeaker. Ambient RF noise or possible interference can be monitored. A steady hissing noise is normally heard. This is the background noise of the radio. Any steady pulsing, low frequency buzzing or even voice traffic indicates an interfering signal that may reduce the maximum range of the system. In most cases the effects of these interfering signals can be reduced or eliminated, but the techniques vary due to type of installation and antennas.