On Tuesday 29 April 2008 04:06, Sjouke Burry wrote:

As a last(distasteful)resort you could discharge a cap
(~1000mfd 10-50volt)between pins with an intermittent
short in the blue gun.

I've decided not to try this. It's dangerous as it is, but especially for
heater-cathode shorts, because you often also blow out the filament.