The negative resistance of the tunnel diode counteracts the positive resistance in the LC tank, causing oscillations to build over time instead of diminishing. 300 MHz oscillator and probe loop ...

When the input signal Vin is positive, Op-Amp output terminal is negative, Diode D1 is reverse biased and D2 Diode is forward biased, the circuit is. Vb = -(R2/R1) * Vin. In the circuit, R1 and R2 ...