Try using this configuration but with a capacitor to tune it into a
parallel circuit and then couple it with a HiZ transformer - about 50
turns of 28 ga on a FT50-61 will get you close to a match into 50 ohms.
The secondary is 3-4 turns of 18-20 ga - connect the primary across the
tuned circuit and peak for maximum gain. Much better gain because you
don't slug the loop with the mismatch - that said, its still benefits from
a pre-ampŠ.
I've used this with tuned loops for DF'ing at many frequencies. Look at:
http://www.n6rk.com/loopantennas/pacificon.pdf
All credit to Rick N6RK for this coupling method in print!
Stu K6TU
On 11/30/12 5:50 AM, "K1TTT" <K1TTT@ARRL.NET> wrote:
>I use a simple loop. A half dozen turns of leftover insulated copperweld
>about 18" in diameter taped to a fiberglass electric fence rod. Directly
>attach rg-58 or 8x coax and wind as many turns as possible through a big
>ferrite to make a choke for the feedline. Gives a nice figure 8 pattern
>but
>pretty low sensitivity. maybe add a preamp for weaker signals? maybe
>more
>turns would be more efficient?
>
>David Robbins K1TTT
>e-mail: mailto:k1ttt@arrl.net
>web: http://wiki.k1ttt.net
>AR-Cluster node: 145.69MHz or telnet://k1ttt.net
>
>-----Original Message-----
>From: N1BUG [mailto:paul@n1bug.com]
>Sent: Friday, November 30, 2012 13:27
>To: rfi@contesting.com
>Subject: [RFI] 160m ARDF / fox hunt antenna
>
>I need a hand held ARDF / fox hunting antenna for 160 meters. It has to be
>small enough to be easily hand carried (preferably for long periods),
>cheap,
>hopefully something I can throw together from assorted bits of junk and
>make
>work acceptably. In other words, I need the impossible? I wish to use this
>with my Alinco DJ-X11T receiver, rather than building a whole receiving
>package. Any plans, links, ideas please?
>
>73,
>Paul N1BUG
>
>_______________________________________________
>RFI mailing list
>RFI@contesting.com
>http://lists.contesting.com/mailman/listinfo/rfi
>
>_______________________________________________
>RFI mailing list
>RFI@contesting.com
>http://lists.contesting.com/mailman/listinfo/rfi
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
|