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From: David Bowman <davidg0mrf@gmail.com>
Date: Mon, 8 Jan 2018 16:27:26 +0000
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To: rsgb_lf_group@blacksheep.org
Cc: "rsgb_lf_group@yahoogroups.co.uk" <rsgb_lf_group@yahoogroups.co.uk>,
        "Discussion of the Lowfer (US, European, & UK) and MedFer bands" <lowfer@mailman.qth.net>
Subject: Re: LF: Great conditions and first QSO
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Hi Paul.

Idea number ????      If your amplifier is oscillating above MF, then you
may be able to tame it by using a series capacitor and resistor between
drain and gate. This will apply frequency dependent negative feedback which
should stop the oscillation. (Not ideal as it shouldn't oscillate
anyway...but a likely fix)

Values are debatable, but 220R (1W) and 1000pF would be a place to start.

73

David

On Sun, Jan 7, 2018 at 12:19 PM, N1BUG <paul@n1bug.com> wrote:

> Congratulations to 2E0ILY, G0LUJ, EB8ARZ/2, K3RWR, and WA3TTS/2 for the
> great trans-Atlantic work last night! Well done all.
>
> After more than a year working toward it, I made my first two-way LF QSO
> with K3RWR. I was proud of myself for convincing the amplifier to put 16
> watts into the antenna without any apparent funny business. Shortly after,
> while trying to set up on WSPR for the night, the amplifier took off and
> blew another FET. I then decided it was a good night for sleeping. :-)
>
> 73,
> Paul N1BUG
>
>
>

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<div dir=3D"ltr"><div><div>Hi Paul.<br><br></div>Idea number ????=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0 If your amplifier is oscillating above MF, then you m=
ay be able to tame it by using a series capacitor and resistor between drai=
n and gate. This will apply frequency dependent negative feedback which sho=
uld stop the oscillation. (Not ideal as it shouldn&#39;t oscillate anyway..=
.but a likely fix)<br></div><div><br></div><div>Values are debatable, but 2=
20R (1W) and 1000pF would be a place to start.</div><div><br></div><div>73<=
/div><div><br></div><div>David<br></div></div><div class=3D"gmail_extra"><b=
r><div class=3D"gmail_quote">On Sun, Jan 7, 2018 at 12:19 PM, N1BUG <span d=
ir=3D"ltr">&lt;<a href=3D"mailto:paul@n1bug.com" target=3D"_blank">paul@n1b=
ug.com</a>&gt;</span> wrote:<br><blockquote class=3D"gmail_quote" style=3D"=
margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Congratulati=
ons to 2E0ILY, G0LUJ, EB8ARZ/2, K3RWR, and WA3TTS/2 for the great trans-Atl=
antic work last night! Well done all.<br>
<br>
After more than a year working toward it, I made my first two-way LF QSO wi=
th K3RWR. I was proud of myself for convincing the amplifier to put 16 watt=
s into the antenna without any apparent funny business. Shortly after, whil=
e trying to set up on WSPR for the night, the amplifier took off and blew a=
nother FET. I then decided it was a good night for sleeping. :-)<br>
<br>
73,<br>
Paul N1BUG<br>
<br>
<br>
</blockquote></div><br></div>

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