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Author Topic: The PWM Amplifier Circuit? Looks easy enough.  (Read 24945 times)

ThaDood

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The PWM Amplifier Circuit? Looks easy enough.
« on: December 20, 2025, 1737 UTC »
https://www.circuits-diy.com/pwm-amplifier-circuit-ca3130-cd40106/    Hmmmmmmmmmmm... 700kHz from their example? Perfect, to boost like a 100mW for an AM Carrier-Current setup. (FWR by Boomer to me.)
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redhat

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Re: The PWM Amplifier Circuit? Looks easy enough.
« Reply #1 on: January 05, 2026, 1253 UTC »
This is a self-oscillating PWM amplifier.  Don't count on the switching frequency being stable, as load profile will change the switching frequency (along with the wind, moon phase, etc).  These are my least favorite of the class D variety, as they can be very finicky and ill behaved.
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