Paul, Stefan,
I you cannot put the coil at the top of the tower there is an
alternative, see http://www.strobbe.eu/on7yd/136ant/#Tower
73, Rik ON7YD - OR7T
At 10:35 30/03/2010, you wrote:
Dear Paul,
I have an idea. Take a photo of tower and the place where the coil will
be placed and add some red lines (e.g. with MS Paint) to illustrate the
wires. Then we can add some lines how we would do it :-)
Can you use the tower itselt as the antenna? I mean, can you place the
coil on the tower and bring some wires down to earth, taking the HV?
That would be the effectivest way to radiate a signal since the most
current will flow in the cable between earth and the lower end of your
coil! It's like on LF, MF and HF, the effectiveness grows when the
loading coils are places as far as possible from the feeding point (e.g.
a short dipole or vertical).
73, Stefan/DK7FC
Am 30.03.2010 00:36, schrieb Paul A. Cianciolo:
> Hi Jim
>
> Thank you for the formula for calculating "C" of a wire.
> Also the information about adding additional wires is valuable.
>
> There are 2 methods I could try with my 55 meters of wire.
> With the use of fiberglass spreaders, multiple wires could be spread apart
> at the top of the tower forming a fan of the wires.
> With a single point on the shack end where the wires would all would
> combine.
>
> Probably better would be to support 4 wires equally spaced on a fiber glass
> poles 9 meters long on both the tower end and the shack end.
>
> This seems too easy Jim, there must be a point of diminishing returns.
>
> Knowing that the wire is 55 meters long, and 1 wire measures at
340 pf would
> you hazard a guess as to 4 wires 1 meter apart each the value of "C"
>
> Do you think 700 pf is achievable?
>
> Thank you for reading
>
> PaulC
> W1VLF
>
>
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