4212D

Directly heated or receiving triode documented by the manufacturer; available source material does not establish a narrower functional category strongly enough for reassignment.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: -
Socket code: LARGE4BAYONET
Base pins: 4
Nominal heater: 14 V / 6 A

Description

Directly heated triode. For replacement purposes only. The 4212-D valve employs an oxidised nickel anode and has been replaced by the 4212-E valve. SPECIFICATION. Cathode. Oxide coated filament. Constant voltage type. Base.

Socket description

Large 4-contact bayonet base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: -
Socket code: LARGE4BAYONET
Base pins: 4
Nominal heater voltage: 14 V
Nominal heater current: 6 A
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

1 physical section, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances

Plate resistance: 2000 Ω
Transconductance: 0.008 S
Amplification factor: 16
Max plate voltage: 2000 V
Max plate dissipation: 200 W
Max cathode current: 300 mA

Published ratings and characteristics promoted where directly established by the datasheet.

Source-dependent data

Operating conditions by source

Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.

Data set 01

1946 Standard Telephone and Cables

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

Mutual conductance
8000 µS
Published characteristic; normalized from mA/V

Other

Anode-filament capacity
6 pF
Published interelectrode capacitance
Maximum direct anode current
300 mA
Maximum safe operating rating