Envelope-to: dave@picks.force9.co.uk
Delivery-date: Wed, 25 Jan 2006 23:07:27 +0000
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From: "g3ldo" <g3ldo@ukonline.co.uk>
To: rsgb_lf_group@blacksheep.org
References: <NKEMLGOEKANPNJOBFBAFGEKDCJAA.g4wgt@tiscali.co.uk> <016101c61d02$12ceca40$2101a8c0@pcroelof> <002b01c61d54$c510aaa0$20347ad5@w4o8m9> <013401c621bd$c7f33c20$2101a8c0@pcroelof> <000001c621d9$6ee29240$67b0fea9@lark> <000b01c621df$f54a2ae0$2101a8c0@pcroelof>
Date: Wed, 25 Jan 2006 23:23:30 -0000
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Subject: LF: Re: Re: Re: Re: Re: Mini Whip and local noise
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Hello Roelof

You said:

>One of the tests I did was on the second floor of a large concrete
community
> building.
> I have performed some height test as well and found the following figures:
>
> height               rel. dB
> =================
> 1.2 m / 4 ft            0 dB
> 2.4 m / 8 ft         + 4 dB
> 3.6 m / 12 ft       + 6 dB
> 4.8 m / 16 ft       + 8 dB
>
> Shielding by bushes in my garden has also been noted. I had to raise it
> above these to restore a good s/n ratio. On the other hand, at an open
field
> near a lake it worked first class 2 metre high and raising it improved
> signal strength but not the signal to noise ratio.
>
These results are in line with tests done by G3GRO a couple of years ago
with a short electrostatic whip antenna.

I have the amplifier and coax voltage supply board for a electrostatic
antenna used at the Decca transmitter sites. The original antenna  was a
copper cylinder fixed only a metre or so above ground. I am not sure what
they were used for - I guess Walter would know.

Peter, G3LDO