Warren
I have not found that to be the case at this qth. Loops are not affected by
trees because there is nothing being radiated to be affected whereas the big
signals from verticals are affected to some degree but most of the rf
escapes to DX locations
I am not aware of any commercial LF or MF station using loops.
Verticals large voltages small current , loops no voltage but large current
causing big losses, especially whey one hears about loops being wound around
big lossy leafy trees.
de mal/g3kev
----- Original Message -----
From: "Warren Ziegler" <[email protected]>
To: <[email protected]>
Sent: Friday, June 11, 2010 3:31 PM
Subject: Re: LF: LF/VLF
Mal,
On 137kHz loops here produce 1W ERP for each 400 Watts of transmitter
output.
I recall someone posting here from the U.K. that his vertical on 137
produced 700 mW ERP with 650 Watts transmitter output so sometimes
loops are superior.
--
73 Warren K2ORS
WD2XGJ
WD2XSH/23
WE2XEB/2
WE2XGR/1
On Fri, Jun 11, 2010 at 10:21 AM, Laurence KL7UK
<[email protected]> wrote:
>
>
> Mal - are you saying small lambda loops are ineffective for dx working at
> LF, say 137Khz? (where within practical verticals give poorer performance
> in wooded areas....or arent feasible).
>
> Past results would not concur; Small backgarden loops producing around 3W
> ERP (on a good day!) have been repeatably seen at >12,000kms - so I beg to
> differ.
>
> Cheers
>
> ________________________________
> From: [email protected]
> To: [email protected]
> Date: Fri, 11 Jun 2010 14:39:17 +0100
> Subject: LF: LF/VLF
>
> All
> Forget about loops, ground rod induction etc if you want to radiate a dx
> signal.The average person could shout and be heard further. A mechanical
> alert/fire siren can be heard several miles away by ear.
> For serious distance DX on vlf a vertical configured antenna is the only
> solution, ie loaded inv L, T ant and some insulated ground radials as long
> as possible.
> one earth spike at the base of the vertical drop wire connected to
radials.
> This is the basic approach and can be fine tuned later once you are making
> progress and being heard/seen a few hundred kilometres away.
> 73 de mal/g3kev
>
>
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