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Hi All,
today I did the first reception test with a matched
antenna. I have spread about 150 meter of wire
(four wires)
sloping from the top of my tower up to about 3
meter off the ground and
with another wire i have reached the shack through
a open window (BRR!! today we have only +2°C).
I have connected the wire to my variometer then i
have connected the "cold" side of the inductance through
a ferrite transformer to ground. I used as a
ground the tubes of heating system of my house plus another wire
connected to eight ground rod.
I could easily tune the inductance and matching
transformer.
Then i have compared the signal level of the
unmatched 80m delta loop withe the antenna on testing.
The results on DCF39 signal (measured at 16,35 UTC)
are:
Unmatched Delta loop -62 dBm with
-97dBm noise floor (S/N 35 dB)
Matched
Marconi -37 dBm with
-94dBm noise floor (S/N 57 dB)
Whereas the four wire of the capacitance hat
sloping close to ground and therefore the effective
height of the antenna is reduced significantly and,
also the vertical part of the antenna is not exactly
vertical, in short for to be an ugly antenna i
think the result is good.
Tomorrow I will do the measurement during daylight
for have a stable result without fading then in next
days i start to build the definitive antenna (with
capacitance hat as little as sloping).
73, Fausto IK4NMF
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