They are almost identical.
Oddly enough the 4cx1500B is rated for both AB1 and AB2 with less output in
AB2 than AB1.
But, bias values are just about the same for both tubes in AB1.
Run AB1 and go for it. CW IMD does not really matter.
The real advantage is that you have 50% more plate dissipation.
73
Bill wa4lav
At 09:50 PM 8/8/2012 -0700, Vic K2VCO wrote:
>Because as I understand it, the tubes are essentially the same except for
>a slightly
>larger anode cooler which accounts for the additional dissipation. The
>parameters for
>typical operation on the 4CX1500B data sheet are based on a load line
>closer to class A
>than those on the 1000 sheet -- they call for lower bias and screen
>voltage and more
>idling current. The intention is to produce much less IMD. Since I'm a CW
>operator, I
>would rather have full legal output than reduce IMD.
>
>On 8/8/2012 9:31 PM, Bill, W6WRT wrote:
> > ORIGINAL MESSAGE:
> > On Wed, 08 Aug 2012 20:06:50 -0700, you wrote:
> >
> >>
> >> I've been thinking about my next project for some time, and I can't
> seem to shake the idea
> >> of an 160-10M amplifier using the 4CX1500B. The tubes and the
> beautiful SK-800B socket are
> >> just burning a hole in my workbench, as it were.
> >>
> >> So I am thinking of running it in AB1 according to the parameters in
> the 4CX1000 datasheet
> >> -- 3kV on the plate, 325V on the screen and -60V bias.
> >
> > REPLY:
> > Why are you using the 4CX1000 data sheet?
> >
> > 73, Bill W6WRT
> > _______________________________________________
> > Amps mailing list
> > Amps@contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
> >
>
>--
>Vic, K2VCO
>Fresno CA
>http://www.qsl.net/k2vco/
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