On Sat,1/7/2017 6:18 AM, David Robbins wrote:
It is interesting that they warn you about that... but a company making a radio
should at least try to choose a wart that is quiet.
Since it has been posted by others that the radio DOES hear weak signals
12 inches from the wart, it strongly suggests that they DID do their
best with choosing the one they did. Some mfrs are more careful than
others in this regard. I've not done exhaustive studies, but the SMPS
units supplied with Thinkpads both before and after IBM sold the line to
Lenovo are generally pretty quiet. I should look at the PSUs supplied
with my Motorola cell phone. The few Apple products in our home also
seem fairly clean. The 33V PSU shipped by SteppIR to run their
controller was a HORRIBLY noisy beast, and not even the most massive
choking could make it acceptable. I replaced it with a home brew linear
supply from the estate of a neighbor ham, whose Rohn 25 sections are 2/3
of what's holding up that antenna.
As to "government regs" and "individual choice:"
1) People are not CHOOSING a power supply, they are choosing an
appliance, and the PSU comes with it. Choice was made by the seller, not
the buyer.
2) The mandate for efficiency came, I believe, from the Dept of Energy,
and is in same spirit as that for high efficiency lighting -- to reduce
our carbon footprint.
3) EMC regulations come from the FCC. Different branch of government.
Left hand does not know what right hand is doing -- or, more to the
point, left hand does not know that the right hand is there.
4) FCC regs are not enforced because the FCC has been seriously
underfunded for several decades. It is Congress that sets funding.
73, Jim K9YC
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