[Antennas] Loop Antennas

[George, W5YR]

Only that because of the extremely high Q of these antennas, the loop must
be made of a very low-loss conductor - MHF uses 1" diameter aluminum
tubing, for example - and the tuning capacitor must have exceptionally low
loss since at 100 watts, the current through the loop and cap can run into
the ten's of amperes and the voltages can become quite high. So I'm afraid
that your #10 wire is out. The MFJ cap uses all-welded split-stator
construction to avoid any moving contacts that would introduce loss.

Steve Yates, AA5TB, is probably the local guru in this area on mag loops.
You might get in touch with him for information.

A lot of work has been done on these antennas - I suggest a Google search
for more info as well as a trip to the ARRL website.

But, you are right about one thing: one that would work well would be
dynamite!

72/73/oo, George W5YR - the Yellow Rose of Texas         
Fairview, TX 30 mi NE of Dallas in Collin county EM13qe   
Amateur Radio W5YR, in the 56th year and it just keeps getting better!
QRP-L 1373 NETXQRP 6 SOC 262 COG 8 FPQRP 404 TEN-X 11771
Icom IC-756PRO #02121  Kachina #91900556  IC-765 #02437

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Bob Wilder wrote:
> 
> The current thread on this list has got me to thinking about rotatable
> loop antennas for 160-40 meters.  I remember back in the '30's and 40's
> most of the radios had a wire loop mounted on a pasteboard back cover.
> 
> My question is this.  Is there a way to build a loop of this type (say out of
> #10 insulated wire) which would work for tranmitting on 160-40 with about
> 100 watts of power.  I figure if it works for receive purposes, it should be
> able to be made to work for transmitting.  Just think about a four foot
> square wire loop on a TV rotator that would work on transmit and be
> able to null out QRM on receive.  Any thoughts on this?