[TowerTalk] What does -db antenna gain mean?

[Jim Brown]

On 8/8/2017 10:08 AM, Bill Straw via TowerTalk wrote:
> According to a Cebik article, a 160M inverted L over 4 x 50' radials has a -2.2 db gain. I think a -3 db gain would mean half the power would go into the ground?

First, you've left off the reference for gain, which is probably "i." 
Antenna gain is usually expressed as dBi, which means dB with respect to 
an isotropic radiator in free space.

Several years ago, I put together a talk on 160M antennas, most of which 
is about radial systems, which is the most important part of a vertical 
antenna, especially for the lower bands.

http://k9yc.com/160MPacificon.pdf

73, Jim K9YC