Tube-number record

7247

1 archive entry

7247 is a tube type in the TubeDatabase archive (class: Dissimilar Double Triode). Recorded specifications: brand General Electric, socket Noval (B9A), maximum plate voltage 330 V, and maximum plate dissipation 3 W. The archive holds 1 photographed example of this type.

BrandGeneral Electric

ClassDissimilar Double Triode

BaseNoval (B9A)

Filament12.6 V @ 150 mA

Construction

Filament / Heater

Heater NotesSeries or parallel connection

Absolute Maximum Ratings

Plate Voltage330 V

Plate Dissipation3 W

Cathode Current22 mA

H-C Voltage100 V

Typical Operation

Mode	Plate V	Gm (µmhos)	Rp (Ω)	µ	Plate mA
Section 1 (Low-level High-gain)	100 V	1250	80000	100	0.5 mA
Section 1 (Low-level High-gain)	250 V	1600	62500	100	1.2 mA
Section 2 (Cathode follower / Phase-inverter)	100 V	3100	6500	20