From: "jannsen" <0482183881-0001@t-online.de>
To: rsgb_lf_group@blacksheep.org
References: <01C227EF.24643850.g4jnt@thersgb.net> <5.1.0.14.0.20020710141708.00ba0208@pb623250.kuleuven.be>
Subject: Re: LF: polarization of small loops
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Date: Sat, 13 Jul 2002 18:27:40 +0200
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Rik Strobbe schrieb:
> Dear LF group,
>
> I have been looking for some information about the polarization of small 
> loops, but no success.
>
> For full-size loops things are quite clear, a loop can be polarized 
> horizontal or vertical depending on the feeding point.
>
> What about small loops ?
> I found several descriptions of small transmitting loops close to ground 
> and there loops were fed at different places (center horizontal side, at 
> the edges). Polarization seems to be vertical in all cases.
> And what about a small loop is free space ? Current distribution is uniform 
> over the entire loop, regardless of the feeding point. So one would expect 
> always the same polarization (but which one ?). Unless also the voltage 
> distribution plays a role.
>
> Anyone who can point me to the right theory and/or has experience with 
> feeding small loops at different points ?
>
> Thanks in advance,
>
> Rik   ON7YD
>
>
Hi Rik es all,

the following may confuse the loop scene still more:

I have a loop 70m long, 12m high and 2m above ground with two windings, 
fed at the lower E (east) edge.
some weeks ago I made a field strength test L-aerial (17m mast and 340m 
longwire 17m to 9m up) contra loop. 
Geri/DK8KW measured the strength using his MV62.
the loop is erected N/E. DK8KW is located S from here.
result: no difference btwn the aerials as Geri reported (both 20uV/m).
so can one say the (my) loop polarizes vertical (non directional) 
if used as TX-aerial?

vv. used as RX-antennas loop to L-antenna was -63dBu to -50dBu (indicated by a 
RYCOM-rx) receiving DK8KW. 

receiving Reino/OH1TN (nearly E) RYCOM indicates no 
difference btwn the two antennas. 

but Reino does not hear me if I do use the loop as TX-aerial.
with the L-aerial conn to the TX Reino gives me regular RST 569.

in abt three weeks I will go to the bottom of it.
I will perform tests in QRSS mode during 
afternoons on 136.0kHz for the purpose of field strength measurements.
distance to the aerials: on average seven km (3xlambda).  
transmitter power output will be 20 Watt, 130 Watt and 800 Watt.  
Aerials: inv. L-aerial and TX-LOOP.

the test will last several weeks. I cant make any schedule.

is the qrg ok? any protests from the bandplaners?

btw. Rik, in ur fine prgr QRS I do miss the possibility keying a 
continuous dash among the text. 

regards
dj8wx/Uwe


regards
Uwe/dj8wx