6F8G Raytheon staggered black ribbed plates used/strong 1940”s (7.6ma and 8.8ma)

6F8G Raytheon staggered black ribbed plates used/strong 1940”s

1 section) 7.6ma Gm=2800

1 section) 8.8ma Gm=2900

Tested on Amplitrex

Vplate=250V

Vgrid=-8V

Good Iplate = 7-10

Good Ma = 2500-2800

NOTES:

6F8G = (2) 6J5G inside 1 bulb

1 section has top cap for grid

1 section has internal grid connection

GE, Sylvania and Raytheon have mirror image parallel black plates

RCA and Ken Rad have staggered black ribbed plates