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On 5/4/2024 3:23 AM, Carlos E.R. wrote:On 2024-05-02 21:34, Don Y wrote:>You can legislate requirements for broadcasters (as a condition of
granting them use of the air waves) mandating they "conduct periodic
tests of (an) emergency broadcast capability". But, you are ultimately
reliant on them to maintain that capability, despite any pressure on
profits, etc.
>
We routinely lose TV reception due to outages on the mountain (where
most of the transmitters are located). Imagine the consequences of
an earthquake or wildfire in areas where transmitters (or repeaters)
are located. Or, hurricane, tornado, flood, etc.
>
Not everyone owns a cell phone -- or keeps it ON for the convenience
of CALLERS! The same can be said of all broadcast media (do I have
to keep a radio/TV ON 24/7/365 "just in case"?
The cell network is very vulnerable to disasters, you can not rely on it.
Especially if the disaster is "local" to the folks you want to inform.
>>AM radio can be leveraged for wide area coverage without requiring
lots of other technology to keep it operational. And, the receivers
can run for long periods of time on batteries (that are likely
stale) or clock-spring mechanisms (emergency radios).
I have seen radios with a hand spun dynamo.
I have one with a clockwork mechanism -- wind up a large spring and
it drives a small "generator" as it unwinds. It takes about 5 minutes
to unwind completely so it's a relatively low "winding" duty cycle.
>
But, it is large-ish.
>
It also has solar cells and a small, internal battery (which is toast;
but, attempting to disassemble it to replace the battery would likely
result in a mess of gears and torsion spring parts!) As the spring mechanism
will run the radio despite the bad battery, it seems a safer plan to just
tolerate the bad battery!
>I saw some electronic magazine publishing one such radio made using the motor>
from a floppy drive (if memory serves) as generator.
>
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