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Power - Triode ·Triode

4220C

Water-cooled directly heated triode documented by Standard Valves for substantial power service; the available source summary does not specify a narrower application.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
22 V / 41 A

Description

The 4220C is a water-cooled 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
22 V
Nominal heater current
41 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
7500 Ω
Transconductance
0.0053 S
Amplification factor
40
Max plate voltage
13000 V
Max plate dissipation
10000 W
Max grid dissipation
200 W
Max cathode current
1.5 A

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

    205 pF

    Published datasheet value

  • Anode-filament capacitance

    3 pF

    Published datasheet value

  • Grid-filament capacitance

    20 pF

    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

    5300 µS

    Published characteristic; normalized from mA/V

Other

  • Anode—filament capacity

    3 pF

    Published interelectrode capacitance

  • Maximum direct anode current

    1.5 A

    Maximum safe operating rating