Hello,
as far as I could remember, several articles cover that topic in 14th.
edition of Hints&Kinks by ARRl.
Basically the short, could be removed by putting appropriate amount of AC
voltage between the grid an cathode. A bulb is in serious with ac/variac and
then by gentle turning and light pounding with wooden stick on surface, the
short could be removed by welding/ dewelding?/ effect. Tube should be
wrapped in towel and of course extreme caution should be paid off.
Please refer to the original article. Please remember : SAFETY FIRST!!
Good Luck Nermin S58DX
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