JB, Alan,
if I recall well this feeding method was tried on 136kHz with success by some
Dutch hams activating a windmill (PI4OSS ?).
73, Rik ON7YD - OR7T
________________________________________
Van: [email protected] [[email protected]]
namens Alan Melia [[email protected]]
Verzonden: woensdag 28 april 2010 16:48
Aan: [email protected]
Onderwerp: LF: Re: Antenna Article
Hi JB there is something similar to this I believe in Rick's ON7YD's web
tutorial on LF antennas.
http://www.strobbe.eu/on7yd/136ant/ look at section 2.12
Is this a case of feeding at an elevated tapping point to get a better
impedance.....very short antennas are very low in impedance at
160........you may find this doesnt work at LF (136 - 180) due to the much
higher ground losses.....interesting experiment though.
Alan G3NYK
----- Original Message -----
From: "John Bruce McCreath" <[email protected]>
To: "& UK) and MedFer bands Discussion of the Lowfer (US European"
<[email protected]>
Cc: <[email protected]>
Sent: Wednesday, April 28, 2010 1:35 PM
Subject: LF: Antenna Article
Hello LFers & Lowfers,
Volume 7 of the ARRL Antenna Compendium has an interesting article by John,
VE2CV, on an electrically small
antenna for 160 meters. He mentions how a virtual inductance can be
created at the top of a tower by means
of "insulating a suitable conductor inside the tower and shorting it to the
tower at some judicious length away
from the end." The top loading wires are attached to the top of this
conductor which extends above the top
of the tower by some distance.
Has anyone here tried this very interesting approach? I don't recall
hearing or reading of this method of putting
an inductor at the top of a vertical section of a top loaded LF antenna.
Being more of a mechanical nature rather
than the usual elevated coil, its losses may be less. I might give it a
try myself just to check it out.
73, J.B., VE3EAR
LowFER Beacon "EAR"
188.830 kHz. QRSS30
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