Re: Care of Rare Valves
Thinking about it, I have often seen this but never considered that it was anything other than a hand assembly error. Do they always lean in the same plane, not sideways or twisted?
Ignoring the obvious valves where the electrode assembly is deliberately set at a steep angle in the envelope, like PX4 etc, would they worry about this when hand making valves?
Could it be simply the annealing process whilst the valve was pumped that caused the assembly to move, being the last hot operation, and they considered that it was not important to the operation of the valve?
Later valves all had mica top supports, perhaps this is why. The change to bulb shape is vital to fitting a top support, in the early balloon shape it is not possible. They had to have a rigid support frame for the electrodes.
Also the heavy over gettering often completely silvered the bulb, hiding the misplaced assemblies, deliberate?
I don't suppose we can find anyone now that was involved with this early production, they would be unlikely to recall it anyway!
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