DeForest Audion SPSG
DC Det/Amp Triode
~1914

This early Audion has a wound type Hudson filament. See the close-up below of the fine tantalum wrapping at the arch of the tungsten filament. This audion was found in the Ultraudion carton shown. Note that the carton label was printed as a 6 volt filament, and has been written over by hand to 3.5 volts.

 Click the back button on your browser to return to the thumbnails