Sujet : Re: High purity 1kHz oscillator
De : bill.sloman (at) *nospam* ieee.org (Bill Sloman)
Groupes : sci.electronics.designDate : 24. Oct 2024, 10:39:03
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <vfd4k0$2j2d5$1@dont-email.me>
References : 1 2
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On 24/10/2024 4:44 am, john larkin wrote:
On Tue, 22 Oct 2024 01:10:41 -0400, "Edward Rawde"
<invalid@invalid.invalid> wrote:
But I suspect that component tolerances and mismatched FETs will ruin it.
The very best bulk metal foil resistors have voltage-resistance
coefficients of a few ppm/volt. Most resistors are much worse.
Metal film resistors aren't all that much worse than bulk foil resistors, and they are pretty cheap aznd widely available.
Just the resistors can kill distortion specs.
Not that you can cite an example
At low frequencies, self-heating and tempco can add distortion too;
Pull the other leg.
The old HP oscillators
had that effect from the lamp filament.
The lamp filaments ran rather hotter.
DGMS on capacitor nonlinearity.
The capacitors and resistors would have to remarkably bad to make much
difference to a well-designed Wein bridge.
You've already got started on making an ass of yourself about resistor non-linearities. Making bizarre claims about capacitors is more of the same.
-- Bill Sloman, Sydney
High purity 1kHz oscillator
Re: High purity 1kHz oscillator