1 tube type 42 Fivre made in Italy old production 1940's
black round plate
copper rods
squared getter
coated glass
brown base
Fat ST shape
yellow label wide on glass
pure pentode for last stage audio or driver tube for exotic project DIY
tested on tube tester TV7D/U = 88 (reference good at 50)
Power Output pentode
42 = UZ-42 = UZ42 = A642 = 42S = W2160 = NU-42 = VT163_GPO = CV1712 = ER42
Similar tubes Other shape (e.g. bulb type): M42
Sub tube: 38042 ; 42E
Other class quality (otherwise equal): 1615 ; CV609
Different maximum ratings: 293A_WE
Heater different: 18 ; 2A5
Other wirings: 6P6_AUS
Other base: 42_Octal ; 6F6G
42 tube is the previous version of 6F6G / 349A WE
Socket is 6-Pin-Base U6A, old, USA
Filament Heater is Vf 6.3 Volt / If 0.7 Ampere / Indirect
box 183
cod 6