On Sunday, 26 June 2011 08:44:15 UTC+10, John S wrote:

Hi, Owen -

Allow me to jump in here and ask: which antennas are less dependent on
ground?

John - KD5YI

Hi John,

Perhaps I might answer by nominating some that are more dependent on ground..

The classic case would be a monopole worked against real ground, meaning having one terminal of the feed line connected to the dirt in some way.

A centre fed dipole rigged very low to real ground is more depended on ground than one that is higher.

My experience is that if you don't have the time or resources to install a substantial ground system, avoid antennas that depend greatly on that ground system for performance. Driving a short conductive stake, or running a wire along the surface, or running a wire into a body of water does not make an effective ground system for these purposes.

I recently had QSO with a field station on 40m at about 500km distance. Initially he had a half wave dipole lying on the ground, and was somewhat surprised that I could work him with 100W from his tx. He raised the dipole to 5m (15') and we tried 50mW SSB. He reported that I was essentially noise free at that, but I could not reduce power any further.

We prove time and time again that anything "works", but an antenna less dependent on the ground usually gives more consistent performance.

Owen