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Power - Triode (over 1000V 100W) ·Triode

4251AX

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
-
Base pins
-
Nominal heater
10 V / 16 A

Description

The 4251AX is a triode described in the Standard Valves datasheet, using a directly heated filament cathode and published operating data.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
-
Nominal heater voltage
10 V
Nominal heater current
16 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
2750 Ω
Transconductance
0.0038 S
Amplification factor
10.5
Max plate voltage
3000 V
Max plate dissipation
1000 W
Max grid dissipation
50 W
Max cathode current
600 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

1937 Standard Valves

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Total emission

    6 A

    Published datasheet value

  • Grid-anode capacitance

    86 pF

    Published datasheet value

  • Anode-filament capacitance

    52 pF

    Published datasheet value

  • Grid-filament capacitance

    12 pF

    Published datasheet value

Other

  • Maximum frequency for above ratings

    30 MHz

    Published datasheet value

Data set 02

1946 Standard Telephone and Cables

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Mutual conductance

    3800 µS

    Published characteristic; normalized from mA/V

Other

  • Grid-filament capacity

    12 pF

    Published interelectrode capacitance

  • Maximum direct anode current

    600 mA

    Maximum safe operating rating