> Couldn't it be that the graphites are totally different material than the
> standard Eimacs?
I'm sure that's 99% of it. Although my old Amperex 8163s will get orange as
well, it just takes them longer which is why I guessed at it being a thicker
material. And likewise it takes quite a while for the exhaust air
temperature to drop.
But as SM0AOM inferred previously, there's graphites and then there's
graphites - the older graphites weren't meant to withstand orange the way
the new graphite design tubes do. I can't remember where I read about
that - the term was "graphite poisoning" and perhaps it was Mr. Measures'
site or thereabouts. I honestly do not remember.
I've foolishly packed my Amperex 8163s away in packing cartons and replaced
them with old Eimac 3-400Z tubes for the sole purpose of viewing their glow
during operation. I get a comfortable 500W in CW position with dull orange
color - those tubes aren't up to the task of a sustained KW on SSB position.
Unfortunately, I don't have enough $$$ to purchase another 7dB so losing the
glow for another 3 or 4dB won't cut it for me.
Although I will say the Acom 1000 I had was VERY nice.
73 Jason N1SU
Jason Buchanan - Boxboro, MA FN42fl
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