See the excellent CWAZ filters by W3NQN in the new edition of the Handbook,
it offers 60 db attenuation of the second harmonic. It offers much greater
performance than the 7 element chebyshev design. It would certainly make
building amplifiers easier not having to worry about the L in the tank
circuit
Craig
VK3HE
----- Original Message -----
From: Peter Chadwick <Peter_Chadwick@mitel.com>
To: 'amps' <amps@contesting.com>
Sent: Tuesday, March 14, 2000 4:17 AM
Subject: FW: SV: [AMPS]Plate choke at the antenna end instead?
>
>
>
>
>
> > Marv says:
> >
> > > I suppose the method could be extended to higher power levels by
> > >employing RG-401 (7.5KV) or if that isn't available, just running some
> > high >voltage / high temperature (silicone) wire through a piece of
tubing
> > before >fabricating the coil.
> >
> > Teflon wire any better/easier?
> >
> > >I've never seen this exact circuit employed in any amateur equipment
> > >nor even described in the literature.
> >
> > I remember you posting that, Marv - it seems exceedingly elegant.
> >
> > With the Radio Regulations demanding 10dB more harmonic rejection than
the
> > current European and FCC specs for new transmitters from 2003, if anyone
> > is going to bother meeting them, Pi-L's won't be good enough, so a plain
> > pi network and a switched simple low pass filter may be the answer. That
> > makes the approach even easier than with a pi-L.
> >
> > 73
> >
> > Peter G3RZP
> >
> >
> >
> >
>
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