The tests that I have made so far tell how well the antennas work indoors with my signals, but I have been searching for a test method that would give a more accurate indication of relative antenna gain.
I have settled on an Antennas Direct DB2E antenna and a Blonder Tongue HAVM-1UA Frequency Agile Modulator for a stable transmitted test signal.
I read about the antenna test measurements done by Kent Britain (WA5VJB). He has made measurements with the test antennas at ground level and above ground level. When the antennas are elevated, the receiving antenna picks up the direct signal and a signal reflected from the ground. I tried it both ways. The ground level signals level are much weaker, but the gain difference between antennas is about the same, so I used elevated antenna measurements. Kent was making measurements at microwave frequencies with horn antennas, see p. 5:
http://www.wa5vjb.com/references/Ant...0Notes-keb.pdf
First I did a comparison between the antennas elevated on tables and on the floor. The HAVM is only for UHF:
Code:
Comparison between antennas on tables and antennas
on the floor for gain comparison measurements.
TABLES FLOOR
Channel GE PRO GE Attic GE PRO GE Attic
29884 34792 29884 34792
dBmV dBmV dBmV dBmV
15 -11.1 -13.4 -20.3 -22.3
28 -10.0 -9.8 -24.9 -23.4
39 -12.1 -12.7 -23.5 -24.2