On 11/20/2023 1:16 AM, Jim Brown wrote:
This is clearly power-handling electronics,
Some tutorial thoughts for those with less technical background, and who
have not taken the time to study enough to have earned their license,
which both requires and depends upon technical competence! We have the
operating permissions we do BECAUSE we supposed to be are technically
competent. I am one of many who studied the ARRL License Manual to pass
our license exams (me at age 14), but the responsible ham goes back and
works to actually LEARN that stuff. For many of us, it led to a career
in some form of electronics or communications. I ended up in
broadcasting and pro audio; others put us on the Moon and Mars. K4BAI
and W6OAT, both of whom I worked fairly often as teenagers, became
lawyers and a bankruptcy judge. At age 82, I'm still trying to learn new
stuff, and all my life I've tried to share what I've learned.
Traditional power supplies rectify to produce half-sine DC, which must
be filtered to produce DC. Because the power frequency is 60 Hz, that
requires larger filter caps (translate to more expensive and large).
Switch-mode power supplies include the traditional power supply, but
then use that DC to produce square waves in the range of 10 kHz; their
period is FAR shorter, so the required filter caps are MUCH smaller, and
cheaper. As one of the earliest measures to save energy, switch-mode
power supplies were mandated by law a couple of decades ago, but
Congress failed to fund the FCC to enforce their own Rules (Federal Law)
that required that they not cause harmful interference. It is safe to
assume that 99.9% of these products are noise generators.
73, Jim K9YC
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