Six transformers are generally available in the radio. 1. Power transformer is used to provide suitable working voltage; 2. High-frequency transformer is used for receiving, selecting, and matching impedance of high-frequency radio waves; 3. Oscillation transformer (also known as local oscillator coil) is used for this machine. Oscillation signal generation and selection; 4, intermediate frequency transformer (also known as mid-week), used for tuning, selection and transmission of intermediate frequency signals; 5, input transformer (also known as audio or low frequency input transformer) for signal decomposition and transmission And impedance matching; 6 output transformer (also known as audio or low frequency output transformer) for signal synthesis, transmission and impedance matching.
All mutual inductance transformers (except self-inductive transformers) have isolation (DC isolation, electrical isolation, etc.).