[VHFcontesting] 3CX800 Tube

[Jim Worsham]

I have a Commander II amplifier that I bought used a few years ago.  The
thing has never put out the 1,000 Watts it is rated at.  Whenever I tried to
get more that 600 or 700 Watts out I could never tune it to keep the grid
current down to an acceptable level (less than 50 mA).  This past week, at
the urging of a friend, I replaced the tube with a spare that I had.  Now I
get 1000 Watts out no problem.  My friend also told me that he had heard
that Eimac had made a batch of 3CX800s that drew excessive grid current and
that this is a known problem.  The date code on the tube is 9926.  By the
way, the tube I replaced it with was a much earlier date code, 9251.  Does
anyone know anything about this?  Did Eimac do anything for the hams that
had these tubes?  Any information would be appreciated.

 

73

Jim W4KXY