Jumbo 4-pin bayonet (1918)
Sidecontact and top contact.
Utilizzata per
Transmittertube (Radio)
Filamento
Vf 5 Volt / If 7.5 Ampere / Direct
Descrizione
This code can be found printed on some tubes manufactured by Heintz & Kaufman: 'Gammatron' was used as trademark by this manufacturer.
4-pin Jumbo base.
