I was thinking maybe I can find some coax that will fit tightly in
copper pipe so that I could use a shield. Do you think that would help
the null?

The reason I need copper pipe is that I need the construction to be
very rigid so that I can accurately align the compass to the loop.

Dale Parfitt wrote:
wrote in message
ups.com...
My s-meter is also a few bars on a LCD, which is why I thought being
able to read the voltage directly would be handy. Now that I think
about it, I can read the S-meter voltage through the serial port.

The difference between the 1ft and 2ft loop is a big deal in that the
smaller loop has deeper nulls and was much more accurate.

There is no theoretical reason why a 1' loop would have any different nulls
than a 2' or 10' loop ( at the freqs we are discussing).
If the nulls are deeper than there is a balance problem with the 2' loop.

I agree- LCD (digital ) S meters are of little value here.
Dale W4OP