" I have noticed that my G5RV picks up about HALF the noise that the
K9AY loops do, and when I try to use my pre-amp (ICE, 1800-2000kHz)
with the loops all it does is amplify the noise. The signal/noise
ratio remains the same, if not lower because now it is louder!!!"
The quote above makes me wonder about how you measured. You need to be
sure that you are not just comparing the absolute levels of noise on
your horiz vs. the K9AY.
Listen to a fairly weak signal in the desired direction on the horiz
ant and note the DIFFERENCE between the desired signal and the noise
on THAT antenna. Then do the same on the K9AY. The K9AY is working for
you if the DIFFERENCE ON THE LOOP is better than the DIFFERENCE ON THE
HORIZ.
Having the preamp on all the time while making a difference
measurement should return the same result as measuring all the time
with it off. If not, use the preamp on/off setting for the antenna
that returns the largest difference.
Except in substantial improvement situations, measuring and comparing
signal/noise usually can't be done well without some equipment, either
a scope (hardware or audio card based) or peak-reading audio voltmeter
calibrated in db's. And, of course, receiver AGC needs to be off.
It would not be at all uncommon for a by-ear comparison of two
signal/noise differences to miss a signal/noise change of four or five
db. Particularly so if the absolute signal levels differ on the two
antennas.
It is better to use equipment to measure signal/noise and let those
measurements "calibrate" your ears over time, than to assume your not
hearing a change means there is no difference.
(Been there, done that, been fooled, shame-on-me, yada, yada.)
73, Guy.
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