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Voltage Pentode or Tetrode (under 100V) ·Diode-Pentode

EAF42

Diode variable-mu pentode for RF, IF, and audio-frequency amplification together with signal detection. The pentode provides controlled gain for AVC while the diode supplies the associated detector function.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
NOVAL
Socket code
B9A
Base pins
9
Nominal heater
6.3 V / 200 mA

Description

Diode-pentode for detection and RF, IF or low-frequency amplification.

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
NOVAL
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

NOVAL - Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

2 physical sections, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
1400000 Ω
Transconductance
0.002 S
Amplification factor
16
Max plate voltage
300 V
Max screen voltage
300 V
Max plate dissipation
2 W
Max screen dissipation
0.3 W
Max cathode current
10 mA

Promoted from clearly identified published ratings/characteristics; additional operating points, capacitances, detector data, microwave data, and special-quality limits are retained in TUBE_SECTION_PARAMETER.

Section 2

Diode

X-ray radiationInterelectrode capacitances
Max plate voltage
50 V
Max cathode current
5 mA
Rectifier peak inverse voltage
350 V
Rectifier nominal output current
600 mA
Rectifier peak forward current
5 A

Promoted from clearly identified published ratings/characteristics; additional operating points, capacitances, detector data, microwave data, and special-quality limits are retained in TUBE_SECTION_PARAMETER.

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

1951 Mullard Valve and Service Manual

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate Supply Voltage

    250 V

    PentodeSection

  • Screen Voltage

    85 V

    PentodeSection

  • Plate Current

    5 mA

    PentodeSection

  • Screen Current

    1.5 mA

    PentodeSection

Characteristic

  • Transconductance

    2000 µS

    PentodeSection

  • Plate Resistance

    1.4 Mohm

    PentodeSection

  • Grid Voltage for 100:1 Transconductance Reduction

    -43 V

    PentodeSection

Data set 02

1963 Philips Electron Tubes Handbook V1a

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate voltage

    250 V

    RFIFAmplifier

  • Screen voltage

    85 V

    RFIFAmplifier

  • Control-grid voltage

    -2 V

    RFIFAmplifier

  • Plate current

    5 mA

    RFIFAmplifier

  • Screen current

    1.5 mA

    RFIFAmplifier

Characteristic

  • Transconductance

    2000 µS

    Section1

  • Plate resistance

    1400000 Ω

    Section1

Capacitance

  • Plate capacitance

    5.2 pF

    Section1

  • Grid capacitance

    4.1 pF

    Section1

  • Grid-to-plate capacitance maximum

    0.002 pF

    Section1

SECTION 2

Diode

Capacitance

  • Diode capacitance

    3.3 pF

    Section2

Other

  • Peak inverse voltage maximum

    350 V

    DetectorDiode

  • Average diode current maximum

    0.6 mA

    DetectorDiode

  • Peak diode current maximum

    5 mA

    DetectorDiode

Data set 03

1967 Mullard Receiving Tubes for Maintenance

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • I

    5 mA

    Published in approved EAF42.pdf target datasheet; Section2

  • Ig ,

    1.5 mA

    Published in approved EAF42.pdf target datasheet; Section2

  • Ik max

    10 mA

    Published in approved EAF42.pdf target datasheet; Section2

  • la d max

    0.8 mA

    Published in approved EAF42.pdf target datasheet; Section2

SECTION 2

Diode

Other

  • I

    5 mA

    Published in approved EAF42.pdf target datasheet; Section1

  • Ig ,

    1.5 mA

    Published in approved EAF42.pdf target datasheet; Section1

  • Ik max

    10 mA

    Published in approved EAF42.pdf target datasheet; Section1

  • la d max

    0.8 mA

    Published in approved EAF42.pdf target datasheet; Section1

Data set 04

1968 Mazda Belvu

Published operating points and test conditions from this source.

SECTION 1

Pentode

Application

  • Application

    RF_IF_AF_Amplifier text

SECTION 2

Diode

Application

  • Application

    Detector text

Data set 05

1999 Philips E-Z

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristics

  • Heater voltage

    6.3 V

  • Heater current

    200 mA

  • Typical plate voltage

    250 V

    RFOrIF

  • Typical plate current

    5 mA

    RFOrIF

  • Typical screen current

    1.6 mA

    RFOrIF

  • Transconductance

    2150 uS

    RFOrIF

  • Plate resistance

    1.4 Mohm

    RFOrIF

Other

  • Maximum plate no-current voltage

    550 V

  • Maximum plate voltage

    300 V

  • Maximum plate dissipation

    2 W

  • Maximum screen no-current voltage

    550 V

  • Maximum screen dissipation

    0.3 W

Capacitance

  • Input capacitance

    4.1 pF

  • Plate-grid capacitance maximum

    0.002 pF

  • Diode-grid capacitance maximum

    0.0015 pF

SECTION 2

Diode

Other

  • Maximum diode inverse peak voltage

    350 V

  • Maximum diode average current

    0.8 mA

  • Maximum diode peak current

    5 mA