70MHz parallel crystal oscillator

The figure shows a 70MHz parallel crystal oscillator circuit. The oscillator is mainly composed of transistor VTl, crystal SJT and capacitors Cl, C5 and other components.

Component selection:

Capacitor Cl is 20p, C2 is 100p, C3 and C7 are 820p, C4 is 56p, C5 and C8 are 47p, and C6 is 47μF/50V.

Inductor L1 is 22μH (color code inductor), L2 is 0.3μH. Resistors R1 is 1.6kΩ, R2 is 1kΩ, R3 is 750Ω, and R4 is

180Ω, 1W, R5 is 1.3kΩ, R6 is 3kΩ, R7 is 360Ω, R8 is 470Ω, R9~R12 are 300Ω, 2W. Transistors VTl and VT2 are 3DG828, 65≤β≤115. Crystal SJT is JA98 type -70MHz. Relay KM is JUC-1M.