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From: markf@amc.UUCP
Newsgroups: sci.electronics
Subject: Re: Phase Jitter of a free-running oscillator
Message-ID: <327@amc.UUCP>
Date: Wed, 18-Feb-87 11:09:51 EST
Article-I.D.: amc.327
Posted: Wed Feb 18 11:09:51 1987
Date-Received: Fri, 20-Feb-87 04:15:39 EST
References: <5246@reed.UUCP> <919@unc.unc.UUCP> <1444@vice.TEK.COM> <5368@reed.UUCP>
Distribution: world
Organization: Applied Microsystems Corp.; Redmond, Wa.
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> How can I obtain large fluctuations in a *low* speed oscillator?  I
> want an oscillator at about 3 kHz with large unpredictable variation
> in the lengths of individual cycles.

Well...

If rectangular waves are OK, you could use a pair of oscillators, set
to relatively prime frequencies.  They could be combined in different
ways for different effects, such as XOR'ing, or using the clock & "D"
inputs of a flip-flop, or "phase comparator II" of the 4046 PLL.

Or, use a VCO, and feed the voltage-control input with a noise source,
say the RC-filtered output of a pseudo-random sequence generator.

Or, a Wein-bridge oscillator, with the resistive-tuning element being a
photocell, pointed at a lava lamp.

Or, use a high-gain amplifier I built some time ago.

Or...

-- 
				Mark S. Freeman
				Applied Microsystems, Inc.
				markf@amc