Coplpitt’s Oscillator in PartSim

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Hi, are you good, I mean really good at mastering the concepts of electronics? Have you ever developed your own circuits, tested and made them function as desired? Then you might want to read this!

This is a common emitter Colpitts oscillator. R1 and R2 form a voltage divider to provide base bias. the emitter resistor R3 also provides some bias. R4 is the collector resisotr across which the any output signals appear. the output is fed into a parallel LC tank circuit. A capacitive voltage divider is used to provide feedback. The cap C3 between the LC dircuit and the base, effectively passes the AC feedback signal but block the DC on the collector. the phase shift on the LC network is 180 degrees from the top of L to the bottom of L.


R1 = 63.4K CMF5063K400FHEB CMF63.4KQFCT-ND RES 63.4K OHM 1/4W 1% AXIAL
R2 = 12K CMF554K1200FHEB CMF4.12KHFCT-ND RES 4.12K OHM 1/2W 1% AXIAL
R3 = 1.2K ERO-S2PHF1201 P1.20KCACT-ND RES 1.2K OHM 1/4W 1% AXIAL
R4 = 4.7k 1622500-1 A105962CT-ND RES 4.70K OHM 0.6W 1% AXIAL
C1 = 1uF EEA-GA1HR10B P15818CT-ND CAP ALUM 0.1UF 50V 20% RADIAL
C2 = 1uF EEA-GA1HR10B P15818CT-ND CAP ALUM 0.1UF 50V 20% RADIAL
C3 = 1mF EKMG250ETD101MF11D 565-3339-1-ND CAP ALUM 100UF 25V 20% RADIAL
C4 = 1uF EEA-GA1HR10B P15818CT-ND CAP ALUM 0.1UF 50V 20% RADIAL
L1 = 3.2mH B82442H1334K 495-3438-1-ND INDUCTOR 330UH 200MA 2220 10%
Q1 = NPN 2N2222A 497-2598-ND TRANS NPN 40V 600MA TO-18
C5 = 1uF EEA-GA1HR10B P15818CT-ND CAP ALUM 0.1UF 50V 20% RADIAL
R5 = 1K CMF551K0000BEEB CMF1.0KHBCT-ND RES 1.0K OHM 1/2W 0.1% AXIAL

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