On Tue, 28 Jun 2016, rickman wrote:

The term "amateur" is often applied to people who have obtained a license to
use radio equipment for communications. Is this term inclusive of those who
don't obtain a license but use receivers for various uses?

I have been looking into design of receivers in the LF to ELF frequency
ranges. Is this part of "amateur" radio?

It's complicated.

One reason amateur radio exists is because once Marconi spanned the
Atlantic with radio, it was out of the lab and people played with it.
There was a time when daily newspapers would have articles about it, so i
gather.

INitially, nobody had a use for radio, that came through use. So when the
Titanic sunk in 1912, the rules were tightened and then later tightended
more. Amateur radio was there from the start, the rules getting tighter
as the years progressed.

So you didn't need a license at first, and then later people started
broadcasting because they were aware more people were playing with radio
receivers than actually had transmitters.

There probably was no distinction initially, but as time went on, yes
"amateur radio" does mean a licensed ham radio operator.

There are people who have similar interests, but not in transmitting (or
they don't want to bother with the license), they are "amateurs" but not
"amateur radio operators" or whatever you want to call them. SOme have
mentioned shortwave listeners, and a subset of that is interested in
building, but I think most SWLers are just interested in receiving, maybe
building small projects to enhance reception.

SOmeone brought up part 15. That may be a grey area. 100mW walkie
talkies on the CB band were part 15, and in the sixties there were even
projects (and commercial units) for improving performance, "you can DX so
long as you keep within the rules", unlike CB that was only intended for
local communication. So those would place the transmitter and integral
antenna up a tower, and then use a decent shortwave receiver for
reception. That gave you height, but the better receiver probably helped
a lot, since those 100mW walkie talkies generally used superregenerative
receivers.

But that wouldn't have classified as "amateur radio".

And in the sixties and seventies there were articles in the hobby
magazines about that 160 to 190KHz band, promoting it as a hobby. Every
few years there'd be an article, often a construction article, but then
nothing. I think it was the late seventies when we'd start to hear about
serious work on that band, though perhaps it just wasn't visible before.
But as someone said, often by hams who were interested in using those low
frequencies. But the users of that band would be called "radio
hobbyists" even though the more serious users probably did have ham
licenses.

Michael