Re: LF: Antennas on low bands : the Siegel and Labus books.

[<riese-k3djc@juno.com>]

 

 

On Fri, 29 May 2015 19:59:23 +0000 Rik Strobbe <Rik.Strobbe@fys.kuleuven.be> writes:

Hi Bob,

 

small is a relative thing on LF.

A DDRR with a perimeter of 0.25 lambda and a height of 0.025 lamdba is indeed small on 144MHz, but on 137kHz the perimeter becomes 550m and the height a respectable 55m.

Not a backyard antenna ...

 

73, Rik  ON7YD - OR7T

 

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Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org] namens riese-k3djc@juno.com [riese-k3djc@juno.com]
Verzonden: vrijdag 29 mei 2015 18:30
Aan: rsgb_lf_group@blacksheep.org
Onderwerp: Re: LF: Antennas on low bands : the Siegel and Labus books.

has anyone tried a DDRR antenna on LF

there is info on them in one of the arrl antenna books and I use one on
144 very small but appears to work as well as a 5/8 wave

appears as a small horziontal loop but radiates as a vert

most odd thing but works well on 2 meters

 

Bob K3DJC

 

On Fri, 29 May 2015 17:19:24 +0200 =?iso-8859-1?B?R3V56SBBbmRy6Q==?= <andre.guye1@aliceadsl.fr> writes:

Hi to all.

 

I see that many questions are on the LF reflector about antennas on low bands, modeling and concerning the lobe formation zones (Fresnel, Fraunhofer and Rayleigh). On the way, that explain why IUT is using the E.I.R.P. as standard of power.