> There isn't a cathode driven 4-1000A in the world at 3500 volts HT
> that can have 13dB gain, unless it has a bad case of positive
> regeneration. A 3CX1200 or 3-1000Z would barely, if at all, make
> that gain.
I have built and operated several 4X1 amps over the years.
On a good day with a good layout and a 100% tube, you can expect
1500 watts key down with 100 watts drive at an Ep of 6000v.
The drive power vs power output is not a linear thing as you
increase Ep.( You get a big kick in efficiency as you go past 5500-5700
volts, just as you can see with an 8877 as you pass 3800 volts.)
Any higher indication would make your wattmeter suspect.
A good tuned input circuit is necessary. The drive impedance
is c. 110 ohms, as I recall. I quit using glass tubes 5 years ago....
life is much more simple now....the ceramic tubes are much easier
to tame, and fewer bad habits.
(((73)))
Phil, K5PC
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