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Voltage - Triode (single) ·Triode

4020C

Directly heated high-mu oxide-filament triode with top-cap grid connection and published audio operating, output, and harmonic-performance data.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B4
Base pins
4
Nominal heater
2 V / 250 mA

Description

Standard Valves 4020C is an oxide-coated directly heated triode. The sheet publishes its filament rating, static constants, interelectrode capacitances, and a table of typical anode/grid/load operating conditions with output and harmonic performance. Oxide-coated filament high-mu triode, medium 4-pin bayonet-thrust base with grid connected to top cap.

Socket description

European 4-pin base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B4
Base pins
4
Nominal heater voltage
2 V
Nominal heater current
250 mA
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
50000 Ω
Transconductance
0.0006 S
Amplification factor
30

Published ratings/characteristics promoted; remaining useful source values represented as parameters.

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

Capacitance

  • Grid-Anode Capacitance

    7.9 pF

    Published specification

  • Anode-Filament Capacitance

    5.3 pF

    Published specification

  • Grid-Filament Capacitance

    5.8 pF

    Published specification

Characteristics

  • Characteristic Anode Current

    0.8 mA

    For impedance/amplification factor/transconductance values

Other

  • Output Voltage Peak

    18.5 V

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-1V; AnodeCurrent=1.26mA; AnodeResistance=43000ohm; LoadResistance=43000ohm

  • Total Harmonics Below Fundamental

    34.5 dB

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-1V; AnodeCurrent=1.26mA; AnodeResistance=43000ohm; LoadResistance=43000ohm

  • Output Voltage Peak

    20.3 V

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-1V; AnodeCurrent=1.26mA; AnodeResistance=43000ohm; LoadResistance=86000ohm

  • Total Harmonics Below Fundamental

    37 dB

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-1V; AnodeCurrent=1.26mA; AnodeResistance=43000ohm; LoadResistance=86000ohm

  • Output Voltage Peak

    20.6 V

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-1V; AnodeCurrent=1.26mA; AnodeResistance=43000ohm; LoadResistance=129000ohm

  • Total Harmonics Below Fundamental

    37 dB

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-1V; AnodeCurrent=1.26mA; AnodeResistance=43000ohm; LoadResistance=129000ohm

  • Output Voltage Peak

    21.4 V

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-1.5V; AnodeCurrent=0.92mA; AnodeResistance=46000ohm; LoadResistance=46000ohm

  • Total Harmonics Below Fundamental

    30 dB

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-1.5V; AnodeCurrent=0.92mA; AnodeResistance=46000ohm; LoadResistance=46000ohm

  • Output Voltage Peak

    25.4 V

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-1.5V; AnodeCurrent=0.92mA; AnodeResistance=46000ohm; LoadResistance=92000ohm

  • Total Harmonics Below Fundamental

    35.3 dB

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-1.5V; AnodeCurrent=0.92mA; AnodeResistance=46000ohm; LoadResistance=92000ohm

  • Output Voltage Peak

    26.2 V

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-1.5V; AnodeCurrent=0.92mA; AnodeResistance=46000ohm; LoadResistance=138000ohm

  • Total Harmonics Below Fundamental

    37 dB

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-1.5V; AnodeCurrent=0.92mA; AnodeResistance=46000ohm; LoadResistance=138000ohm

  • Output Voltage Peak

    12.1 V

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-2V; AnodeCurrent=0.64mA; AnodeResistance=52000ohm; LoadResistance=52000ohm

  • Total Harmonics Below Fundamental

    21.7 dB

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-2V; AnodeCurrent=0.64mA; AnodeResistance=52000ohm; LoadResistance=52000ohm

  • Output Voltage Peak

    14.8 V

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-2V; AnodeCurrent=0.64mA; AnodeResistance=52000ohm; LoadResistance=104000ohm

  • Total Harmonics Below Fundamental

    28 dB

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-2V; AnodeCurrent=0.64mA; AnodeResistance=52000ohm; LoadResistance=104000ohm

  • Output Voltage Peak

    17.6 V

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-2V; AnodeCurrent=0.64mA; AnodeResistance=52000ohm; LoadResistance=156000ohm

  • Total Harmonics Below Fundamental

    30.5 dB

    TypicalOperatingConditions; PlateVoltage=130V; GridBias=-2V; AnodeCurrent=0.64mA; AnodeResistance=52000ohm; LoadResistance=156000ohm

  • Output Voltage Peak

    24 V

    TypicalOperatingConditions; PlateVoltage=160V; GridBias=-1.5V; AnodeCurrent=1.63mA; AnodeResistance=41000ohm; LoadResistance=41000ohm

  • Total Harmonics Below Fundamental

    35.2 dB

    TypicalOperatingConditions; PlateVoltage=160V; GridBias=-1.5V; AnodeCurrent=1.63mA; AnodeResistance=41000ohm; LoadResistance=41000ohm

  • Output Voltage Peak

    30.2 V

    TypicalOperatingConditions; PlateVoltage=160V; GridBias=-1.5V; AnodeCurrent=1.63mA; AnodeResistance=41000ohm; LoadResistance=82000ohm

  • Total Harmonics Below Fundamental

    38.2 dB

    TypicalOperatingConditions; PlateVoltage=160V; GridBias=-1.5V; AnodeCurrent=1.63mA; AnodeResistance=41000ohm; LoadResistance=82000ohm

  • Output Voltage Peak

    35 V

    TypicalOperatingConditions; PlateVoltage=160V; GridBias=-1.5V; AnodeCurrent=1.63mA; AnodeResistance=41000ohm; LoadResistance=123000ohm

  • Total Harmonics Below Fundamental

    38.5 dB

    TypicalOperatingConditions; PlateVoltage=160V; GridBias=-1.5V; AnodeCurrent=1.63mA; AnodeResistance=41000ohm; LoadResistance=123000ohm

  • Output Voltage Peak

    37 V

    TypicalOperatingConditions; PlateVoltage=160V; GridBias=-2V; AnodeCurrent=1.28mA; AnodeResistance=44000ohm; LoadResistance=44000ohm

  • Total Harmonics Below Fundamental

    29 dB

    TypicalOperatingConditions; PlateVoltage=160V; GridBias=-2V; AnodeCurrent=1.28mA; AnodeResistance=44000ohm; LoadResistance=44000ohm

  • Output Voltage Peak

    42 V

    TypicalOperatingConditions; PlateVoltage=160V; GridBias=-2V; AnodeCurrent=1.28mA; AnodeResistance=44000ohm; LoadResistance=88000ohm

  • Total Harmonics Below Fundamental

    35 dB

    TypicalOperatingConditions; PlateVoltage=160V; GridBias=-2V; AnodeCurrent=1.28mA; AnodeResistance=44000ohm; LoadResistance=88000ohm

  • Output Voltage Peak

    45.6 V

    TypicalOperatingConditions; PlateVoltage=160V; GridBias=-2V; AnodeCurrent=1.28mA; AnodeResistance=44000ohm; LoadResistance=132000ohm

  • Total Harmonics Below Fundamental

    36 dB

    TypicalOperatingConditions; PlateVoltage=160V; GridBias=-2V; AnodeCurrent=1.28mA; AnodeResistance=44000ohm; LoadResistance=132000ohm

Data set 02

1946 Standard Telephone and Cables

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater/filament voltage

    2 V

  • Heater/filament current

    250 mA

  • Plate resistance

    50000 ohm

  • Transconductance

    0.0006 A/V

  • Amplification factor

    30