On 10/10/2012 11:48 PM, Jeff Liebermann wrote:
On Tue, 9 Oct 2012 12:33:16 -0700 (PDT), Lasse_radio
wrote:

I have a groundplane antenna tuned at 125 MHz for the airband
and a newly made QFH for NOAA POES. The QFH is inferior compared
to my GP. It should be the other way around, that QFH should
be a lot better than the GP.

True, for most parts of the sky, except for directly overhead where
the GP has a big null. You should get about 3dBi from both the GP and
QFH antennas. The difference is that the QFH will not have any cross
polarization losses, while the ground plane automatically has a -3dB
loss from the conversion from RHCP (NOAA-19???) to linear vertical
polarization.

Excuse my pedantry, but -3dB loss is actually a 3db gain.

John