Basic radio transmitter circuit consisting of a surface acoustic wave resonator (SAW)

Relevant key device information applied in this article: C3356 C3355 (a) Shown is the basic circuit of a transistor ultra-high frequency radio transmission composed of a surface acoustic wave resonator (SAW), in which the SAW is temporarily used as a positive feedback element connected to the transistor VT The base of the transistor is connected in parallel with the LC network. (b) Shown is another basic circuit of a transistor ultra-high frequency radio transmission composed of a surface acoustic wave resonator. In this circuit, the SAW is connected to the base and emitter of the transistor. between them; the phase relationship between them is 180o, which meets the phase conditions for oscillation. This circuit is a capacitor three-point oscillation circuit. Its oscillation frequency should be determined by the feedback capacitors C1 and C2. Now that SAW is connected, the oscillation frequency of the circuit is determined by the resonant frequency of the SAW, and C1 and C2 are only used as feedback for oscillation. Components do not determine the oscillation frequency of the circuit.