[Lowfer] Worthwhile going to Shielded loop?

[John Andrews]

Paul,

My only experience with shielded receiving loops has been with small,
multi-turn versions. There were no significant reductions in noise, and the
extra capacitance did narrow the tuning range.

But I haven't played with a larger, single-turn shielded loop. I'd defer to
Jay's experience on that one. He and I have produced similar signal reports
with our respective antennas. Mine is unshielded, with 14 turns on a 6 foot
square. The turns are an inch apart. I'd suspect that Jay's antenna delivers
more signal (+noise) to the preamp, though. I tried my "Ashlock" loop for
receiving on 137 kHz last winter, and found that despite the greater signal
(+ noise), I wasn't copying anything better than I could with the smaller
loop. It did offer the possibility of eliminating the preamp, though.

John A.