In article ,
(Mark Keith) wrote:

Jim" wrote in message
...
You can build your own but it's actually not worth it.
--
Ron Hardin



I beg to differ about loops that you build are not worth it.
I designed and built many MW loops that are as good or better in some ways
that the Kiwa loop. The problems with homemade loops is poor construction.
This link has pictures of loops that I built.
http://www.frontiernet.net/~jadale/M...20Antennas.htm

Jim

I agree....My homemade loops are better for my uses than what you can
buy. I can design any feature I want, and generally they are bigger
and deliver more voltage than most storebought. I built two more loops
yesterday just farting around. "Both for longwave". Maintaining
balance is the secret to success. Also, I did an experiment on mine a
couple of days ago. I've been using a simple coupling loop on mine
lately, but do have a shielded coax coupling loop also. "IE: the coax
shield is cut in the middle at the top". One had mentioned an
advantage to using a shielded loop vs a non shielded. Well, I tried
both feeding my 12 turn 16 inch round loop. No difference whatsoever
in noise, or null depth. I had never noticed much difference with
single loops of each type either if you were careful to detail.
So far, I have not been able to see much of an advantage to a shielded
loop vs unshielded as long as you are careful with balance. They seem
to work about the same here.

The shield is electrostatic and would only help against local noise
(example - in the room computer) being the pickup loop.

If you had an un-tuned broadband amplified single turn shielded loop
compared to one that was not shielded then you would expect to see a
difference.

Loop antenna is a broad term.
Here are some features:
1. Small or large compared to the received wavelength.
2. Shielded or not.
3. Single or multi turn and shape type example - pancake or solinoid.
4. Tuned or un-tuned.
5. Several ways to couple them to the receiver.

Now you can mix and match the 5 above into many possibilities all with
different tradeoffs.

--
Telamon
Ventura, California