Schematic for a Simple 218 Hz Astable Multivibrator

Schematic for a Simple 218 Hz Astable Multivibrator

Designed for the Transistor Multivibrator Experimentation Board, this circuit is a great introduction to transistor-based oscillators and multivibrator operation.

BOM (Bill of materials)

C1, C2: 100 nF (2x)
JP1, JP2, Out-D1: Bridged (1x/3x)
Q1, Q2: 2N3904 (2x)
R1, R2: 2.2 kΩ (2x)
R3, R4: 33 kΩ (2x)

Version 2 of the PCB is coming this autumn and includes:

* Breadboard-friendly input and output pin header footprints

* Less visual clutter for beginners

* Improved labeling

See the downloadable schematics and BOM:

PDF