Althougt uncommon on tubes because of the high impedances and the
typical tuned outputs, a class B push pull broadband amplifier has
advantages in a lower harmonic content and with the more simple and
cheap output filtering required, expecially if the transformer output
is already designed to meet the nominal output impedance (i.e 50 OHm).
73,
Mauri I4JMY
> ---------- Initial message -----------
>
> From : owner-amps@contesting.com
> To : <firson@Radiolink.net>, "AMPS" <amps@contesting.com>
> Cc :
> Date : Tue, 25 Jul 2000 06:13:02 -0700
> Subject : Re: [AMPS] PushPull
>
>
> >
> >Some friend told me that runing tube on pushpull will be give bigger
power
> >than parallel (for two tube). I don't really understand, could
anybody here
> >give some explanation.
> >
> This theory is yet another old wives' tale on ham radio. The engine
for
> linear service is peak cathode emission. With two tubes in parallel,
you
> get twice as much peak emission, but the tubes are cut-off for 1/2 of
the
> cycle. For band-changing, parallel tubes are much less trouble than
> push-pull.
>
> cheers, Firson
>
> - Rich..., 805.386.3734, www.vcnet.com/measures.
> end
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