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Re: [linrad] A simple front end


KK7B described some easy ways to get the 90' phase shift, I believe in his
article "High Performance Direct Conversion Receiver"  in Aug '92 QST.   You
can get the required phase shift with L/C networks. I thought I remembered
that article on the web somewhere, but I just spent a couple of minutes
googling around for it and came up empty.

-Joe KM1P
----- Original Message -----
From: "W6WO" <ron-skelton@xxxxxxxxxxx>
To: <linrad@xxxxxxxxxxxxxxxxxxxxx>
Sent: Thursday, August 07, 2003 11:43 AM
Subject: [linrad] A simple front end

> I am keen to experiment with the "very easy way to get 40 kHz of
> radio spectrum into a PC" that Leif described in Fig 2 of the Jan/Feb
> 2003 QEX. My interest is only the cw end of 20 meters
> For an RF stage I plan to use a Mini-Circuits ERA-5 amplifier with a
> band-pass filter ahead of it. Instead of the quarter wave of coax the
> SPH-16 voltage controlled phase shifter looks like the way to go
> unless I can find a cheaper solution. I looked for low noise audio
> ICs that were not surface mount and the best I can find is the LM833.
> Initially I will use a signal generator for the LO but a crystal osc
> would make it a self-contained front end that could be packaged in
> quite a small box.
> I would like to share work of this kind with others, either via the
> list or direct.
> --
> 73
> Ron
> W6WO