A friend of mine called recently and told me he was cleaning out his basement
and sending me some of his old tubes. One was a 250TH. I got it last night.
It was packed very well, along with other tubes. The box arrived with no
damage.
However, when I unpacked the 250TH, I noted that the metal stem above the plate
had fatigued, causing the plate to be loose inside the still good glass. I
believe the damage was fatigue because the tube was laying on its side, rather
than being shipped vertical. I recall a few years ago, I shipped some old
tennis ball Western Electric 205D tubes on their side. The top internal
structure is supported by a vertical glass rod. They were shipped on their
side and all had broken glass rods, even though the tube envelope was still
good.
I expect modern tubes do not suffer this fate, and there is always the problem
that what is shipped vertical is not likely to remain vertical during shipment.
So, this is just a word of caution.
73, Colin K7FM
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