6F8G RCA Radiotron staggered black ribbed plates used/good 1940's (9.0/7.2ma)

6F8G RCA Radiotron staggered black ribbed plates used/good 1940's

1 section) 9.0ma Gm=2800

1 section) 7.2ma Gm=2600

 Tested on Amplitrex

Vplate=250V

Vgrid=-8V

Good Iplate = 7-10

Good Ma = 2400-2600

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