Tony Duell wrote:
If you
build something yourself (which would obviously then
meet the "maintainability" requirements), you could throw
Well, I am not going to make the radio modules myself (no way can I meet
type approval, even if I meet the technical specs)
Y'know, I remember electronics kits as a kid always seemed to include both an
AM transmitter and receiver project...
The Philips EE series of kits had reciever projects, but I don't think
there was a single transmitter. Many other kits did, indeed, have
low-power AM radio transmitter projects
I'm sure they weren't legal, even back then -
unless there is (or was) some
loophole for devices with really limited range/power.
I am pretty sure they were technically illegal in the UK (I don't know
about other countries [1]), but that given the very low range (you were
lucky for it to work across a room), and the fact it wasn't likely to be
in operation for very long, then the chances of getting caught were
essentially 0 (I certainly never heard of anyone having problems ffrom
uilding such projects).
[1] Although I remember a warning in the manual for one such kit which
was something like 'Connecting a long antenna to this project will
violate FCC rules'
Longer-range devices, used for longer periods, as here, are a different
issue, of course.
-tony