John:
That sounds like a W1FB preamp that was in QST in August 1988.
I have the article and will scan it for you if you want.
73 Price W0RI
----- Original Message -----
From: "W0UN -- John Brosnahan" <shr@swtexas.net>
To: <topband@contesting.com>
Sent: Sunday, June 18, 2006 9:15 AM
Subject: Topband: Preamp info wanted
>I ran across an old preamp in my junk box and I am trying to
> find the source of the design, so I can modify it for AM BC DX.
>
> It has an MPF102 JFET first stage and an MC1350 8-pin DIP
> IF amp chip second stage. (Way too much gain.) The front has
> a gain pot as well as a toggle switch to select between two
> input toroidal coils with compression trimmers. One set for
> 160M and the other for 80M. The output has a toroidal core
> transformer.
>
> It is built on a circuit board and clearly assembled by ME since
> the panel is in my handwriting. But I don't recall where the
> design came from.
>
> I have to think it was in some popular magazine or handbook,
> and it must have been a serious enough project for someone
> to make circuit boards available. I probably built this in the
> mid/late 1980s or so.
>
> Much of my library is still at the Colorado QTH so I have been
> unable to do a complete search of my own data. Anyone have
> any idea where this was published and can anyone steer me to
> a copy or scan it for me?
>
> Thanks -- John W0UN
>
> It has been suggested that it might be the KD9SV design -- but that
> is a single stage IGFET rather than this 2-stage JFET/IC design.
>
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