Hi Dick,
The LK2000 was designed to be compatible with the 4-1000A; All the grids are
grounded.
A 4-1000A, in strapped GG, doesn't have quite the gain of a 3-1000Z.
An experimental fellow might add a touch of negative grid bias and some screen
voltage to match the operating point & gain of a 3-1000Z whence the input
impedance would be essentially equal. Said supplies would need to provide
considerable current as operation would remain in AB2.
Probably easier to just tweak the input networks.
A couple of references for this discussion...
The schematic of the LK2000 may be seen here:
http://wc6w.50webs.com/wc6wamps/index.html?fr511.html
The operational data for a 4-1000A in GG may be viewed via this link:
http://wc6w.50webs.com/wc6wamps/index.html?fr56.html
73 & Good morning,
Marv WC6W
http;//wc6w.50webs.com/
--- On Fri, 7/3/09, RICHARD SOLOMON <w1ksz@q.com> wrote:
> From: RICHARD SOLOMON <w1ksz@q.com>
> Subject: Re: [Amps] 4-1000A in LK2000
> To: "Amplifier Reflector" <amps@contesting.com>
> Date: Friday, July 3, 2009, 8:29 PM
>
> Can I ask a dumb question ??
>
>
>
> What do you do with the Screen Grid ?
>
>
>
> Don't you need an additional screen supply ?
>
>
>
> 73, Dick, W1KSZ
>
> > Date: Fri, 3 Jul 2009 20:26:01 -0700
> > From: wc6w_amps@yahoo.com
> > To: klahaie@centricata.com;
> amps@contesting.com
> > Subject: Re: [Amps] 4-1000A in LK2000
> >
> >
> >
> > Hi Kevin,
> > The input impedance of a 4-1000A in "strapped"
> grounded grid is circa 110 ohms.
> >
> > A 3-1000Z runs around 65 ohms.
> >
> > Some input network tweaking will be necessary with a
> transistorized driver.
> >
> > 73 & Good evening,
> > Marv WC6W
> >
> > http://wc6w.50webs.com/
> >
> >
> > <snip>
> > >
> > > Is the input impedance that different from the
> 3-1000?
> > >
> > > 73 Kevin K7ZS
> >
> >
> >
> >
> > _______________________________________________
> > Amps mailing list
> > Amps@contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
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