It appears that your tank coil inductance is too high.
For an operating Q of 12 the tank circuit capacitance would be in the 180 - 200
pF range and
the associated inductance in the 8.5 - 9 uH range (about 2/3 the number of
turns)
With the given coil data, the inductance is in the 20 - 22 uH range, and the Q
will be too low
for an usable impedance transformation.
A suitable procedure would be to adjust the inductance for resonance, using a
dip meter, with the tuning capacitor about 80 % meshed and the loading
capacitor fully meshed. This will work for a start.
73/
Karl-Arne
SM0AOM
----- Original Message -----
From: "The Bowers" <thebowerz@comcast.net>
To: <amps@contesting.com>
Sent: Monday, February 05, 2007 8:56 PM
Subject: [Amps] 807 transmitter
> Has anyone built "K5DH's 807 CW transmitter" (Google) ? I've built just the
> amp section but can't get it to load. I'm driving it with a sig gen at 3.9
> KC.
>
> According to the on line calculators, L3 is at 10.3 uh, but should be 18.5
> uh., for 75 meters.
>
> Has anyone found an error here, or is it just me?
>
> Thanks guys, I appreciate the help.
>
> Dana, W6TUO
>
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> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
>
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> 14:04
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