>...snip... I have in my hand a 7 page, stapled, yellow at the top, 8 x 11 data
>sheet that has Eimac all over it, which states on page 2 at the bottom
>under 'absolute maximum ratings': 'GRID DISSIPATION ..........25 WATTS'
>
>The date is copyright 1970, 71, 73, 75 by Varian (Revised 7-1-75)
>
>You can say what you want to qualify your answers, and maybe it's valid,
>but I see right here in front of me, 25 watts.
>
>For every example of different classes of operation, it is still 25
>watts max.
>
It's 25w max. on my Eimac Technical Data for the 8877, Steve.
- Since the typical grid to cathode. driving voltage is roughly 50Vrms,
it would take a moderate number of grid mA to exceed the 25w max. grid
dissipation specification.
- There appears to be a lot of technoblather floating around about the
extreme delicacy of the 8877's grid. However, at the maximum ratings of
250MHz, 1A, and 4000V, over 40 rms amperes of RF current flows through
the grid to chassis ground/common.
Rich---
R. L. Measures, 805-386-3734, AG6K
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