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Date: Thu, 15 Oct 2015 18:29:11 +0100
Message-ID: <CAA8k23SEnMoQ4J9HQN3aicTNFsy_kN-ReW=1xTmEMCWpO-Kh8w@mail.gmail.com>
From: Andy Talbot <andy.g4jnt@gmail.com>
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You could use a latching relay, and pulse the supply with reverse polarity
to set teh input short.
(Suitably protecting the preamp electronics with a diode)

'jnt

On 15 October 2015 at 18:14, John Andrews <w1tag@charter.net> wrote:

> One trick that I have used on several preamps:
>
> Put a small PC-mount relay (such as those used on telephone lines) at the
> front end of the preamp. Connect the



>  German ops who hang such electronics in distant tree-tops would probably
> not be interested.
>
> John, W1TAG
>
>

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<div dir=3D"ltr">You could use a latching relay, and pulse the supply with =
reverse polarity to set teh input short.=C2=A0<div>(Suitably protecting the=
 preamp electronics with a diode)</div><div><br></div><div>&#39;jnt</div><d=
iv class=3D"gmail_extra"><br><div class=3D"gmail_quote">On 15 October 2015 =
at 18:14, John Andrews <span dir=3D"ltr">&lt;<a href=3D"mailto:w1tag@charte=
r.net" target=3D"_blank">w1tag@charter.net</a>&gt;</span> wrote:<br><blockq=
uote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc =
solid;padding-left:1ex">One trick that I have used on several preamps:<br>
<br>
Put a small PC-mount relay (such as those used on telephone lines) at the f=
ront end of the preamp. Connect the=C2=A0</blockquote><div>=C2=A0</div><blo=
ckquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #c=
cc solid;padding-left:1ex">=C2=A0German ops who hang such electronics in di=
stant tree-tops would probably not be interested.<br>
<br>
John, W1TAG<br>
<br>
</blockquote></div><br></div></div>

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