MOSFET gate depression test oscillator circuit diagram

The output of the grounded outflow Colpitts oscillator uses an RCA N-channel dual-gate FET. Q1 is sensed by CR1 and amplified by Q2, which can be used to drive the oscillator . The oscillation frequency is determined by C1, C2, C3 and L1. When L1 is reduced, the frequency can reach 250MHz. The table gives the values ​​of plug-ins L1-C1-C2 in 9 frequency ranges. The default power supply voltage of the circuit is 12V, but it can also work normally with a 9V power supply. If a leakage resistor Rd is used, the circuit will be short-circuited. Battery consumption is approximately 20mA. All coils are wound in the form of Mirren 45004.