08-29-2012, 07:46 PM
I would think that a heater to cathode short would show on most testers, but you could try with an ohm meter between the cathode pin and either of the heater pins to see if they is a low resistance reading. Heater to cathode shorts are usually something you see in a power output tube but anything is possible. I still find the voltage distribution strange.
Regards
Arran
Regards
Arran