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From: Bill Sloman <bill.sloman@ieee.org>
Newsgroups: sci.electronics.design
Subject: Re: Oscillators in LTspice
Date: Sat, 19 Oct 2024 15:26:20 +1100
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On 19/10/2024 3:33 am, Cursitor Doom wrote:
> Gentlemen,
> 
> I've never spiced an oscillator AFAICR. Do they self-start in spice
> simulators (LT in particular)? IOW, did Mike Engleheart build something
> into the engine which generates wideband 'background' noise, particularly
> at 'power up' as it were? I'm assuming there must be some such mechanism
> and if there is, it must be present by default for all schematics one
> attempts to simulate and not just oscillators?

They don't usually self-start. Rounding errors in the arithmetic do act 
as a source of wide-band noise, but for any practical simulation you set 
up the initial conditions to launch the oscillation at an appreciable 
fraction of the steady state amplitude.

-- 
Bill Sloman, Sydhey