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Author Topic: The PWM Amplifier Circuit? Looks easy enough.  (Read 456 times)

Offline 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.)
“I am often asked how radio works. Well, you see, wire telegraphy
is like a very long cat. You yank his tail in New York and he
meows in Los Angeles. Do you understand this? Now, radio is
exactly the same, except that there is no cat.”
-Attributed to Albert Einstein, but I ripped it from the latest Splatter .PDF March 2025 issue.

Offline 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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