[sdiy] Greetings and Oscillations

[Neil Johnson]

Hi,

A simpler circuit to the one you describe is the single op-amp astable
multivibrator, using both negative and positive feedback to control the
op-amp.

A web intro page is here:

http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/square.html

One op-amp, three resistors and a capacitor.  And don't forget the power
supply too!  The main output is a square wave, but you can also pull out a
rough sawtooth from across the capacitor.

Cheers,
Neil

--
Neil Johnson :: Computer Laboratory :: University of Cambridge ::
http://www.njohnson.co.uk          http://www.cl.cam.ac.uk/~nej22
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