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Voltage Pentode or Tetrode (under 100V) ·Pentode

EF97

Variable-mutual-conductance RF pentode for controlled RF/IF amplification and mixer service. Its gain-control characteristic is central to receiver operation, while mixer capability is secondary rather than a dedicated oscillator-converter function.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
MINIATURE
Socket code
B9A
Base pins
9
Nominal heater
6.3 V / 200 mA

Description

Variable-mutual-conductance RF pentode for RF/IF amplifier and mixer service.

Socket description

Small-button Noval 9-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
MINIATURE
Socket code
B9A
Base pins
9
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
60000 Ω
Transconductance
0.0019 S
Max plate voltage
50 V
Max screen voltage
50 V
Max plate dissipation
2.5 W
Max screen dissipation
0.2 W
Max cathode current
6 mA

Published ratings/characteristics promoted from the approved source.

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

1958 Mullard Receiving Tubes

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristics

  • Transconductance

    500 uS

    Va=6.3V

  • Plate resistance

    200 kOhm

    Va=6.3V

  • Transconductance

    1100 uS

    Va=12.6V

  • Plate resistance

    200 kOhm

    Va=12.6V

  • Transconductance

    2100 uS

    Va=25V

  • Plate resistance

    50 kOhm

    Va=25V

Other

  • Mixer conversion conductance

    655 uS

    RFMixer; Vb=25V

Data set 03

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

    1900 µS

    RForIFAmplifier

  • Plate resistance

    60000 ohm

    RForIFAmplifier

Other

  • Plate voltage

    25 V

    RForIFAmplifier

  • Screen voltage

    6.3 V

    RForIFAmplifier

  • Grid bias

    -0.85 V

    RForIFAmplifier

  • Plate current

    2.7 mA

    RForIFAmplifier

  • Screen current

    0.8 mA

    RForIFAmplifier

Data set 04

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 voltage

    50 V

    Promoted published datasheet value

  • Maximum screen voltage

    50 V

    Promoted published datasheet value

Characteristic

  • Plate resistance

    60000 Ω

    Promoted published datasheet value

  • Transconductance

    1900 µS

    Promoted published datasheet value

  • Chauffage: indirect. Alimentation sé- Ve =

    6.3 V

    Published datasheet value

  • Heizung : indirekt. Serien- oder Pa- If =

    300 ma

    Published datasheet value

  • Heater voltage ¥f =

    6.3 V

    Published datasheet value

  • Heater current Ir =

    300 mA

    Published datasheet value

  • except anode Cgy =

    6.2 pF

    Published datasheet value

  • except grid No.1 Cg =

    3.8 pF

    Published datasheet value

  • Anode to grid No.1 Cagy =

    0.015 pF

    Published datasheet value

  • Anode voltage Va = 25 12,6

    6.3 V

    Published datasheet value

  • Grid No.2 voltage Vg2 = 6.3 6,3

    3.2 V

    Published datasheet value

  • Grid No.1 voltage V81 = -0,85 -0.85

    -0.85 V

    Published datasheet value

  • Anode current Ig = 2.7 2.5

    0.8 mA

    Published datasheet value

  • Grid No.2 current Igo = 0.8 0.9

    0.3 mA

    Published datasheet value

  • Mutual conductance S = 1.9 1.8

    0.9 mA/V

    Published datasheet value

  • Equivalent nolse resistance Rgq = 5 5.5

    8 kΩ

    Published datasheet value

  • Grid No.1 voltage Vg1 = -3.3 ~3.3

    2.6 V

    Published datasheet value

Capacitance

  • Ca = i

    4 pF

    Capacitances

  • Cagl =

    0.015 pF

    Capacitances

  • Cgig2 =

    3 pF

    Capacitances