It´s the opposite.
The required capacitance of the load-C of a simple Pi network is much larger
then that of a Pi-L, a big advantage beside the much besser harmonic
supression and easier tuning.
The two coils should not couple to keep the harmonics as low as calculated.
However, the required inductance is larger with the Pi-L.
73
Peter, DJ7WW
-----Original Message-----
From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com] On
Behalf Of Jim Garland
Sent: Montag, 18. Juni 2012 17:57
To: amps@contesting.com
Subject: [Amps] Pi-L Network Question
I've been noodling around various tank circuit possibilities for a 160m
monoband amplifier. A pi-L network isn't very practical for an 8877 because
the relatively high plate impedance mandates very large values of C1 and C2.
For an 8877, a simple pi-network is preferred. On the other hand, a Pi-L
makes a lot of sense for, e.g., three 3CX800a7s or GU-74Bs, because the
combined plate impedance is under 1000 ohms and the required capacitance and
inductance values are quite reasonable.
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