[HomeBrew] Pixie II Output Filter

[Michael Tauson]

On Mon, Mar 22, 2010 at 10:58 AM, Eugene Crist <ejcristjr at gmail.com> wrote:
> I'm building a Pixie II from scratch for 40m and I want to build a second
> one for 20m. Besides the crystal I'll have to replace L3, the inductor in
> the output filter. According to the instructions, it says to use the formula
> f=1/(2*PI*(SQRT(LC))), but when I use this formula I come up with different
> resonant frequencies than what the transceivers are supposed to operate.

Instead of treating the caps as being in parallel, see how it turns
out if you look at them in series.  A pi-net can be viewed as a
parallel resonant circuit with the capacitor grounded at some point
for impedance matching.  This puts the capacitors in series and makes
a huge difference.

Just a thought through a med-induced haze.  :-D

Best regards,

Michael, WH7HG
-- 
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