I could compare them using about 15 minutes of NEC modeling. I'm quite sure as to which configuration would win, already.
Maybe a volunteer will appear to do the real world tests described (sorry, not me).
but it sure gets the brain going.
Some of us have wondered about
magnetic transmit loops. I don't
know about the length measurement
with regard to Part 15.219...
Brooce
In HB's transmitter challenge the Rangemaster broadcasting on 1640 acheived just a hair under a full mile with an umodulated signal, ground mounted and using a single ground rod with no radials in an area of only .5 ground conductivity.
I tell you what, I must be doing something wrong - even though I'm presently elevated and ungrounded, lately I've been wondering if my now 15 year old 102" fiberglass whip has lost it's gusto or something.
However, the area which Bills challenge took place appears to have been a wide open feild area without buildings or other obstructions, or power lines and so forth, which is quite different than being surrounded by all that stuff.
...Point being that a ground mounted legal install should substantially outdo an elevated legal install.
From Reply #17: Some of us have wondered about magnetic transmit loops. I don't know about the length measurement with regard to Part 15.219...
Brooce - Probably a "legal" case could be made for using a circular loop antenna for transmitting under Part 15 AM, as long as the circumference of that circle plus the length of any other radiating wires used with it don't exceed the 3m limit of §15.219(b).
But unfortunately, a small (in terms of wavelength) loop antenna is not a very efficient radiator -- quite a bit _worse_ than a base-fed, linear conductor such as a ~ 3m whip.
Here is a link to some resource material about this:
http://www.aa5tb.com/loop.html
Interesting information - - I do
appreciate it.
I have been working with receiving loops
for the AM BCB and shortwave for a long
time. I'd like to try transmitting Part 15 AM with one some day. I'd like to try
all of the things you guys are talking about actually.
Brooce
Tim in Bovey has an elevated Procaster mounted outside his house. Uses no ground and covers his small town as well as the town next door quite nicely.