You are absolutely right about the size of the loop.

A larger loop might not enhance the ability to copy a weaker signal.
And, I spent a small fortune in buying big wire just to make it have a
reasonably high Q. My question about the caps was merely to make sure
that I was buying the right type of caps, so that the investment in
the larger sized wire didn't get negated by having the wrong type of
cap.

At some time I might like to evaluate a smaller loop against the big
one in terms of the actual weak signal reception capability.

The receiver is hot on HF and should be just as good on LF and VLF.

Ultimately I'd like a shielded loop, but the effect of the stray
capacitance seems to really kill the Q. The shielded loop camp makes a
convincing argument in that the magnetic field is significantly
quieter than the electrical field is. But, how to do a shielded loop
without knocking the Q all to Hell is a significant issue. Needless to
say the potential for interference by strong LF broadcasters is much
reduced by shielding the loop as well.

One user I spoke to recently commented on the quality of reception
with his shielded loop.....signals that were buried in noise by quite
a few db seem to pop up into Q5 readability when the shielded loop
antenna is switched in. So, I know they work. Just not sure how to
implement them without incurring a lot of loss in Q from the stray
capacitance introduced by the shielding.

T


On 25 Oct 2005 09:22:10 -0700, "K7ITM" wrote:

Another set of questions: Given the high atmospheric noise level at
LF/VLF, is there really a need for such a large loop as you propose,
for receiving? How quiet is your receiver front end? In other words,
will such a large loop significantly improve your SNR on weak signals?
Do you have a reason other than signal level for using such a large
loop? What about the response to nearby strong electric-field noise
generators of a large loop versus a smaller one?

Cheers,
Tom