On Fri, 17 Dec 2004 09:53:31 -0500, Ken wrote:

(1) Will performance improve if I replace the feedline with coax or
shielded audio cable? I would rather not because that would
substantially increase bulk.

Hi Ken,

No, not at the short lengths you describe (and you would need to add
an RF choke at the far end to make the investment in coax useful).
You might want to think in terms of RG-174 if you do want to go coax.

The radio and antenna are ungrounded. Is anything to be gained by
running one side -- the side to BNC jack shield -- to the AC mains
ground or the local plumbing?

Sure, it will add to the length of the antenna (the ground path will
undoubtedly be a substantial length wrt wavelength). By the same
token, it could add just as much (or more) noise.

73's
Richard Clark, KB7QHC