Gasparik Richard schrieb:
Hi LF-ers...
I have build an loop antenna (project of DF3LP). I find that the
sensitivity of the loop with preamp is very low. DFC39 is normaly 50-60dB
over S9 on my LW antenna, but with loop antenna it's 30dB less. I tuned it
for the maximu with serial caps. Directivity is very good (more than 40dB at
90 degrees). It's normal or not ?
73 de Rich OM2TW
Hi Rich, Peter es all
I built Peters loop but changed it in four steps. at the end it was a uge
copper-pipe rotary octaeder 15,2 m round. 4,6 to 5,0 m in diam.
from step to step the nulls got clearer.
but the main reason for building such a monstrum was: With the smaller ones I
could not receive for example SVX, i.e. the sensitivity was bad, ur observation,
Rich. today I am vy proud of this magnetic loop: never before had such a nice
s/n ratio on lf. I will do some measurements conc. the s/n ratio. but guess I
have to wait until winter.
pse have a look at
www.qsl.net/dj8wx/00010.html.
BTW. have had heavy thunderstorm the last days. xyl: there was
a "kugelplitz" in the garden. next day I controlled the magnetic loop. black
marks on the pipesurface es some soldering drops I did not notice before but
nothing damaged.
ah, whats "kugelblitz" on english? flash of lightning biting its tail?
regards
Uwe/dj8wx
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