A Tunnel diode oscillator with wide tuning range (0.7-4.9 Gc/s)

The tunnel diode is coupled weakly to a relatively high Q resonator essentially of the hybrid, or re-entrant coaxial, type. This construction ensures a wide tuning range and a frequency of oscillation that is relatively insensitive to temperature change, supply voltage variations and interchange of diodes. In the basic form of the oscillator, using a 2 mA peak current germanium diode, stable and continuous oscillation is sustained over the full tuning range of 0.7 to 4.9 Gc/s with a power output greater than 1 ¿W up to 4 Gc/s. Alternative forms of the oscillator still under development give power outputs approaching 1 mW at some cost in tuning range.