Date: Sun, 14 Apr 2019 17:08:48 +0100
From: Chris Wilson <dead.fets@gmail.com>
Message-ID: <592014641.20190414170848@gmail.com>
To: DK7FC <rsgb_lf_group@blacksheep.org>
In-Reply-To: <5CB35457.9060303@posteo.de>
References: <477297345.20190414143742@gmail.com> <5CB35457.9060303@posteo.de>
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Subject: Re: LF: Another impedance matching question. Paul's audio amps.
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Hello DK7FC,

I  have about 17 acres to play with, mainly woodland but with a 5 acre
field  and  a big front garden. I thought an aerial antenna would be a
none  starter  due  to  the voltages involved, so I'll be looking at a
ground  loop  for  sure. Here's a link to an aerial plan of what I can
use, but I am going to need some basic advice to get going I am afraid
:)

Links  to  what  you have in mind for ferrite cores would assist in me
having a clearer view of what's involved here please. Thanks Stefan.

http://www.chriswilson.tv/newbury.jpg

Sunday, April 14, 2019, 4:40:07 PM, you wrote:

> Hi Chris,

> What are you planning? Building a ground loop into your garden will be
> the only way to put that power into the antenna. At VLF and your E field
> antenna, you would have to deal with several 10 kV if you actually want
to run >> 1 kW. However on a ground loop, the amplifier will be the 
> limiting factor :-)
> How much space to you have between the electrodes? All you will need is
> a series C to resonate the antenna.
> Use a big ferrite transformer to match the output impedance to the 
> antenna impedance.
> Always use a series C on the primary side of the transformer, if bridged
> or not, to avoid any damage due to an eventual DC-component.
> Use a big ferrite core with just enough primary turns as necessary.
> Now its time for Andy to post the formula again.

> 73, Stefan

> Am 14.04.2019 15:37, schrieb Chris Wilson:
>> Hello  LF'ers
>>
>>   Having  collected my audio amp from Paul Nicholson (VERY many thanks
>>   Paul, it's an awesome looking beast.... :)) I would appreciate anyone
>>   else getting one posting their thoughts and results matching the input
>>   and  output for VLF usage.   Both for antenna and ground comms usage.
>>   Thanks.
>>
>>    


-- 
Best regards,
 Chris                            mailto:dead.fets@gmail.com