[Lowfer] New Loop NG

[Peter Barick]

LowFERs,
Re: My New Loop Ain't Working

I built a new loop late last fall, even had it up on a mast at 20 feet
but _not_ connected. Then the uninvited Minnesota winds came and
prevented further outside work. I took it down.

This weekend it was Texas-like outside and I resumed efforts testing
the loop, which includes a tuning box with a group of switchable caps in
series w/ the loop and a 1:1 LF balun. This was new, the series tuning,
as other loops I tried were parallel tuned. I had everything outside
including my receiver so I could experiment "on the spot." The loop was
in a stand, 7 feet high at center. Oh, as a standard, a test antenna of
40 feet of wire thrown into a tree at one end, was used. I knew of a NDB
in S. Wis. over 100 miles away at about 200 kHz and used it as a tuning
target.

My results were not good and very disappointing. The loop barely copied
the NDB that was heard at abt S4 on the wire. So here's the setup. The
loop is 5-pointed, about 6-feet dia. It's spider-wound and started w/ 27
turns, no. 22 covered wire. I couldn't seem to find a noise peak in the
100-300 kHz range so I removed 4 turns, leaving 23. this seemed to
resonate about 200 kHz using around 200 pfs for tuning. The sig was now
equal to the wire but I found no expected sharp peak for resonance. It
seemed the wire had won this race.  It loop did exhibit directional
properties, however. Yea!

I tried one thing different, a 1-turn pick-up loop 3 inches inside the
mail loop. This produced a stronger signal level when fed directly into
the coax to the rx. Then the balun didn't make a difference when
bypassed or not, still series tuned, as before.
 
Anyone see a problem with all of this? I'd like some tips to possibly
try for next weekend when I'll give it a fresh go.

Left out of this, for now, is a mast-located pre-amp that is to follow
the 1:1 balun. I won't use it until I feel the loop is working
properly.

Peter