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Message-ID: <010b01c6bd86$56689680$bdc828c3@captbrian>
From: "captbrian" <captbrian@ukonline.co.uk>
To: <rsgb_lf_group@blacksheep.org>
References: <000801c6bd7e$c7a2c4e0$63be3b3e@fujitsu>
Date: Fri, 11 Aug 2006 21:40:07 +0100
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Subject: LF: Re: antenna: how to get max. capacity
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By all means put a wire in the middle for extra pf. but the z shape will
make no difference I think.

Make the vertical of three parallel conductors , each to the centre of each
top wire

Bryan g3gvb


----- Original Message -----
From: "Dick" <knaap159@zonnet.nl>
To: <rsgb_lf_group@blacksheep.org>
Sent: 11 August 2006 20:45
Subject: LF: antenna: how to get max. capacity


Hello all,

In order to test my 136kHz TX at home, I just have installed a toploaded
wire in the backgarden.

It measured only 135pF, which is too low, because need around 10mH to get
that running on 136......

System is as follows:

2 wires each 7.5m long mounted parallel (spacing 30cm), at both ends
connected together, and in
the center connected together.
>From the center an about 7m long wire goes vertical downward to the TX.

Any suggestions how to get more capacitance in the air?

I am limited in options, because the topload has an maximum length of 7.5m,
and maximum width of 1m.

Some ideas I have:

-opening up the ends
-adding a third wire in de middle, feed it there and then bending the rest,
a kind of Z-shapped topload, center fed.

Would be happy to get 40 - 50pF extra up in the air.......


73

Dick, PA4VHF