[Lf] [Fwd: LF: Top-loading]

[Andre' Kesteloot]

Alan Melia wrote:

>  Hi all some interesting replies again on this subject. However if you with
> to increase the capacity of the aerial I would not have thought stacking
> extra top wires vertically would be much use, as they would effectively mask
> one another (in my view). Because the other 'Plate' is the ground under the
> aerial, you need more area in the sky parallel to the ground plate to
> increase the capacitance surely. There may be some 'fringing effect' but it
> will probably not be worth the effort, and it would be better to put one
> wire as high as possible. A slim wooden yoke to support two wires is not
> that difficult and they dont have to be pretty and parallel, but can be in a
> V format as mine are.
>
> As Jim says the loss situation is very much biassed by the kind of ground
> you have and the surroundings.....unless you are putting your aerial up in
> the middle of a field, it becomes a unique situation, and you will have to
> experiment (I recommend a simple RX bridge at 136kHz, if you can't lay your
> hands on an old professional unit that modern engineers don't know how to
> use!)
>
> I found that the extra top load, that I erected, gave a significant increase
> in the received signal, due (so Mike tells me) to probably increasing the
> effective height of the aerial. The extra capacitance also makes it easier
> to tune.
>
> Go on ....have a play Stewart!
>
> Cheers de Alan G3NYK
> Alan.Melia at btinternet.com