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Voltage Pentode or Tetrode (under 100V) ·Pentode

EF98

Low-voltage pentode for oscillator, RF/IF amplifier, mixer, and transistor-driver service directly from 6–24 V supplies. Its broad low-voltage amplifier role outweighs any single radio-converter application.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
MINIATURE
Socket code
B7G
Base pins
7
Nominal heater
6.3 V / 200 mA

Description

Low-voltage pentode for oscillator, RF or IF amplifier, mixer, or transistor-driver service from 6 V, 12 V, or 24 V batteries.

Socket description

Miniature 7-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
MINIATURE
Socket code
B7G
Base pins
7
Nominal heater voltage
6.3 V
Nominal heater current
200 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

MINIATURE - 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

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
90000 Ω
Transconductance
0.0021 S
Max plate voltage
50 V
Max screen voltage
50 V
Max plate dissipation
0.5 W
Max screen dissipation
0.5 W
Max cathode current
15 mA

Promoted ratings and characteristics are taken from the printed target-tube entry in the approved PDF.

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

1953 La Radiotechnique

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • HeaterVoltageNominal

    6.3 V

    Nominal

  • HeaterCurrentNominal

    300 mA

    Nominal

  • Maximum Plate Voltage

    250 V

  • Maximum Screen Voltage

    250 V

  • Maximum Plate Dissipation

    2.5 W

Characteristic

  • Transconductance

    5000 µS

    Typical

Data set 02

1963 Philips Electron Tubes Handbook V1a

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • Heater voltage

    6.3 V

    Published heater rating

  • Heater current

    200 mA

    Published heater rating

  • Transconductance

    2100 µS

    IFAmplifier

  • Plate resistance

    90000 ohm

    IFAmplifier

Other

  • Plate voltage

    25 V

    IFAmplifier

  • Screen voltage

    6.3 V

    IFAmplifier

  • Grid bias

    -0.75 V

    IFAmplifier

  • Plate current

    2.2 mA

    IFAmplifier

  • Screen current

    0.6 mA

    IFAmplifier

  • AF-driver power output

    30 mW

    AFDriver

Data set 03

1967 Mullard Receiving Tubes for Maintenance

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • Plate voltage

    12.6 V

  • Screen-grid voltage

    6.3 V

  • Plate current

    2 mA

  • Screen-grid current

    0.7 mA

  • Transconductance

    2 mA/V

  • Plate resistance

    200 kOhm

Other

  • Plate voltage

    12.6 V

    TransistorDriver TetrodeConnection

  • Power output

    11 mW

    TransistorDriver TetrodeConnection

  • Conversion conductance

    675 uA/V

    RFMixer 12.6V

  • Maximum plate voltage

    50 V

  • Maximum plate dissipation

    0.5 W

  • Maximum screen-grid voltage

    50 V

  • Maximum screen-grid dissipation

    0.5 W

  • Maximum cathode current

    15 mA

Capacitance

  • Input capacitance

    6.7 pF

  • Output capacitance

    4 pF

Data set 04

1981 Russian Tubes Katsnelson and Larionov

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • Heater voltage

    6.3 V

    Published nominal/basic-parameter heater condition.

  • Heater current

    300 mA

    Published heater current.

  • Plate current

    1.85 mA

    Published basic-parameter operating point.

  • Screen current

    0.55 mA

    Published basic-parameter operating point.

  • Transconductance

    2000 µS

    Published basic-parameter value; normalized to µS.

  • Plate resistance

    200000 Ω

    Published internal/plate resistance.

  • Amplification factor

    4.3

    Published amplification factor.

  • Input capacitance

    6.7 pF

    Published in the filename-designated tube entry.

  • Output capacitance

    4 pF

    Published in the filename-designated tube entry.

  • Grid-to-plate capacitance

    0.015 pF

    Published in the filename-designated tube entry.

Other

  • Maximum plate voltage

    30 V

    Published limiting operating value.

  • Maximum screen voltage

    30 V

    Published limiting operating value.

  • Maximum cathode current

    15 mA

    Published limiting cathode-current value.

  • Maximum plate dissipation

    0.5 W

    Published limiting plate-dissipation value.

  • Maximum screen dissipation

    0.5 W

    Published limiting screen-dissipation value.

Data set 05

1999 Philips E-Z

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Heater voltage

    6.3 V

    Heating

  • Heater current

    300 mA

    Heating

  • Maximum plate dissipation

    0.5 W

    Promoted published datasheet value

  • Maximum screen dissipation

    0.5 W

    Promoted published datasheet value

  • Vg = max

    50 V

    Limiting values

  • Vep =max

    50 V

    Limiting values

  • Vg2 =max

    0.5 W

    Limiting values

Characteristic

  • Plate resistance

    90000 Ω

    Promoted published datasheet value

  • Transconductance

    2100 µS

    Promoted published datasheet value

  • ries supply Ve =

    6.3 V

    Published datasheet value

  • parallele ou série Ir =

    300 mA

    Published datasheet value

  • Vg2 = 6,3 6.3

    32 v

    Published datasheet value

  • Vgi 1) = -0,75 0,75

    -0.8 V

    Published datasheet value

  • Ia = 2,2 2

    0.6 mA

    Published datasheet value

  • Ig2 = 0,6 0,7

    0.2 mA

    Published datasheet value

  • Ri = 90 200

    100 kΩ

    Published datasheet value

  • Vg2 = 12,6 12,6 14 6,3

    7 V

    Published datasheet value

  • Vg3 = 25 12,6 14 6,3

    7 V

    Published datasheet value

  • Vg1 1) = -2 -2,3 -2,4 “1,2

    -1.3 V

    Published datasheet value

  • Ta+Ig3 = 3 2,1 2,5 1,1

    1.2 mA

    Published datasheet value

Capacitance

  • Ca =

    4 pF

    Capacitances

  • Cg1 =

    6.7 pF

    Capacitances

  • Cagi =

    0.015 pF

    Capacitances

  • Cgige =

    3 pF

    Capacitances