[morzh]

Before you spring for a new 71A try resoldering the filament pins, some of those older tubes have bad solder joints by now.
Regards
Arran

Thanks, Arran.

(I actually bought a pair - not too expensive and the guy claimed he tested them on Hikock; he specializes in tubes and his feedback was 100% so I trust him).

I looked inside the tube - the filament's gone (the two tensioners are up in the air - they should be sunk inside, holding the filaments), so it is not really fixable.

But, hey - thanks, it never occurred to me this could actually happen, so in the future I'll keep that in mind and will be checking it.

Mike.