[AMPS] For who well know 8877

[Alfredo Rosati I5UXJ]

i have an 8877 has carved this acronym ewm282 ( is date code ??)
of which I do not know the history , used or not used (apparently new).
I use it in an amplifier with stripline on 2 meters.
confronting the result with the tecnical given of the 3/15/89
the difference that I find is in the grid current 

Eimac told 3500 volt , 1Amp , 64 watt input , 2075 watt output ,74 ma
grid. (at 30 mhz)

my result are :

3500 volt , 1Amp , 70 watt input , 2025 watt output ,120 ma grid.

i had tried also as data sheet of eimac told for 88-108 operation
at 2000 ,2500, 3000 , 4000 volt.

the is the same more grid current than the data sheet.

i had tried some different output circuit but little difference.

the tube is capable with 100 watt input , to draw 1,5 amp. and an output
of 3700 watt (at 4000 volt).

the question is :
is my tube exausted ? 
is my tube defective ?

people that working in brodcast fm , has told me , that they use
amplifier at 2500 watt whit 80~100 ma grid
2000 watt 40~60 ma grid


If I disalign the load coming down from 2000 watt to 1800 the grid
current go down to around 40 ma.

thank in advance of eventual answers
hello i5uxj

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