At 10:37 am ((PDT)) Mon Jun 18, 2007, ewdawso_1 wrote:
Thanks for your input.
In another thread: Loop antenna with coil
It really does help make sense of things
to keep them in threads, especially for
anyone foolhardy enough to visit the
Messages archive expecting to find
something sensible there.
(It's there- it's the finding that's difficult ;-)
So: one topic per thread and
one thread per topic, please,
until the (regrettable) natural
subject drift kills it.
When I looked at those photos I at first
thought it was for transmitting, however the air capacitor kind of
threw that out for me.
I still think it's for transmitting, just
not much power or there'll be sparks.
That isn't a puny capacitor, but it's not
easy to estimate the airgap from the photo.
Since the loop antenna I am building (my
first) is for listening to am only it will be without the coil.
Yes, there doesn't seem to be a lot of purpose
to accurate receiver matching at MF or HF, unless
it's a crystal set and antenna power is all you have.
The common techniques are:
a) a coupling loop
- for a multi-turn loop, less turns,
often a single turn,
- for a single-turn loop, a smaller size
usually one-fifth the diameter; or
b)a high-impedance preamp.
Regards, LenW
