The next test that I did was to compare the GE PRO, ANT 751R, and the ANT 7511.
Code:
Relative Gain Comparison of three Antennas
Channel GE PRO RCA RCA
29884 ANT751R ANT7511
dBmV dBmV dBmV
15 -10.2 -12.5 -15.6
28 -10.4 -11.6 -13.4
39 -12.0 -12.3 -16.3
Equipment Used:
Antennas Direct DB2E source antenna
3 antennas to be compared
Blonder Tongue HAVM-1UA Agile Modulator
20 dB attenuator to reduce HAVM output
Sadelco DisplayMax 800 Signal Level Meter
Test Conditions:
Indoor Test Range; ground floor, carpet over concrete slab
Antennas 10 wavelengths apart
Antennas elevated on Table-Mate tables
Signal Level Meter measuring analog video carrier
Conclusions:
The GE PRO 29884 antenna is the best of the 3 antennas for my indoor location. The RCA ANT 751R is a close second. The RCA ANT 7511 is third. The RCA design change has sacrificed considerable UHF gain.
I have a little more confidence in these measurements, but there are reflections that will introduce errors. I miss my outdoor range with stable LOS signals.
Quote:
I'm fascinated by your test equipment!
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So am I. Making antenna measurements is one of my favorite things.
You don't need a lot of expensive equipment. With just a variable attenuator and a TV, you can measure margin to dropout of the signal. The simplified form is shown in my signature link.