Hallo Petr,
this morning I compared my L-antenne (6x25m, up 8 to 10m) with the
portable loop (24 turns, 0.6 x 0.6m) by receiving the "big gun" on 128.930
MHz (exact?). Both were carefully tuned to that frequency.
L-antenna: 30,0mV
Loop : 0,25mV both at 50ohm
Maybe you can make a comparison like this? 73 Walter JN59NO
-----Ursprüngliche Nachricht-----
Von: Petr Maly <[email protected]>
An: 136 group <[email protected]>
Datum: Montag, 10. Januar 2000 17:50
Betreff: LF: Bad experience with loop ant
Hello LowFers.
I have made loop ant for rx and it seems not to work satisfactorily. Size
is
1.75m x 1.75m. Everything is done as usual, with grounded middle and
amplifier with 2 x BF245, tuned properly, etc. Output level from the
amplifier is high enough. I can hear Greek RTTY, also galloping horses a
little, but no poor HAM sigs. My LW 40m, that is in average height of about
6 m only, is much better. The only thing I am in doubt is the number of
turns. It has got only 18 turns (I used flat cable that was available at
the
moment). Could this be reason for the bad results? What are your
experiencies with loop ant? Can loop ant be as good as "big" Marconi?
73! Petr, OK1FIG
|
