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Voltage - Triode (with diode, heptode or hexode) ·Diode-Diode-Triode

EBC81

Double-diode high-mu triode for radio receiver detection and audio-frequency voltage amplification. Two diodes provide detector and related rectification functions while the triode supplies resistance-coupled audio gain.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
3
Base
NOVAL
Socket code
B9A
Base pins
-
Nominal heater
6.3 V / 230 mA

Description

Dual-diode triode for detection and low-frequency voltage 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
-
Nominal heater voltage
6.3 V
Nominal heater current
230 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

3 physical sections, each with unique specifications.

Section 1

Diode

X-ray radiationInterelectrode capacitances
Rectifier peak inverse voltage
350 V
Rectifier nominal output current
0.8 mA
Rectifier peak forward current
5 mA
Rectifier max heater-cathode voltage
100 V

Source-published values promoted where directly stated; additional values retained in parameter table.

Section 2

Diode

X-ray radiationInterelectrode capacitances
Rectifier peak inverse voltage
350 V
Rectifier nominal output current
0.8 mA
Rectifier peak forward current
5 mA
Rectifier max heater-cathode voltage
100 V

Source-published values promoted where directly stated; additional values retained in parameter table.

Section 3

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
58000 Ω
Transconductance
0.0012 S
Amplification factor
70
Max plate voltage
300 V
Max plate dissipation
0.5 W
Max cathode current
5 mA

Source-published values promoted where directly stated; additional values retained in parameter table.

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

1963 Philips Electron Tubes Handbook V1a

Published operating points and test conditions from this source.

SECTION 1

Diode

Capacitance

  • Diode capacitance

    0.9 pF

    Diode1

SECTION 2

Diode

Capacitance

  • Diode capacitance

    0.9 pF

    Diode2

SECTION 3

Triode

Other

  • Plate voltage

    250 V

    AudioAmplifier

  • Control-grid voltage

    -3 V

    AudioAmplifier

  • Plate current

    1 mA

    AudioAmplifier

Characteristic

  • Transconductance

    1200 µS

    Section1

  • Amplification factor

    70

    Section1

  • Plate resistance

    58000 Ω

    Section1

Capacitance

  • Grid capacitance

    2.3 pF

    Section1

  • Plate capacitance

    2.3 pF

    Section1

  • Grid-to-plate capacitance

    1.2 pF

    Section1

Data set 02

1967 Mullard Receiving and Amplifying Valves

Published operating points and test conditions from this source.

SECTION 1

Diode

Other

  • Maximum Anode Current

    800 uA

    EachDiode

  • Maximum Peak Anode Current

    5 mA

    EachDiode

  • Peak Inverse Voltage

    350 V

  • Nominal Output Current

    0.8 mA

  • Peak Forward Current

    5 mA

  • Interelectrode Capacitance Data Published

    1

    SourceTablePresent

SECTION 3

Triode

Characteristic

  • Plate Voltage

    250 V

    TriodeSection

  • Grid Voltage

    -3 V

    TriodeSection

  • Plate Current

    1 mA

    TriodeSection

  • Transconductance

    1200 uS

    TriodeSection

  • Amplification Factor

    70

    TriodeSection

  • Plate Resistance

    58000 ohm

    TriodeSection

  • Plate Resistance

    58000 ohm

  • Transconductance

    1200 uS

  • Amplification Factor

    70

Other

  • Maximum Heater-Cathode Voltage

    100 V

    TriodeSection

  • Maximum Plate Voltage

    300 V

  • Maximum Plate Dissipation

    0.5 W

  • Maximum Cathode Current

    5 mA

  • Interelectrode Capacitance Data Published

    1

    SourceTablePresent

Data set 03

1968 Mazda Belvu

Published operating points and test conditions from this source.

SECTION 1

Diode

Application

  • Application

    Detector text

SECTION 3

Triode

Application

  • Application

    AFVoltageAmplifier text

Data set 04

1972 Philips Receiving Tubes

Published operating points and test conditions from this source.

SECTION 1

Diode

Other

  • Diode voltage, negative peak -Vdp max

    - to 350 V

    Maximum

  • Diode current,average Iq max

    - to 0.8 mA

    Maximum

  • Cathode to heater voltage Vkf max

    - to 100 V

    Maximum

SECTION 3

Triode

Other

  • Anode voltage Va 0 max

    - to 550 V

    Maximum

  • Va max

    - to 300 V

    Maximum

  • Anode dissipation Wy max

    - to 0.5 W

    Maximum

  • Cathode current Ik max

    - to 5 mA

    Maximum

  • Grid resistor Rg max

    - to 3 MQ

    Maximum

  • Cathode to heater voltage Vit max

    - to 100 V

    Maximum

Data set 05

1999 Philips E-Z

Published operating points and test conditions from this source.

SECTION 1

Diode

Other

  • Maximum diode current

    0.8 mA

  • Maximum diode peak voltage

    200 V

Capacitance

  • Diode 1-heater capacitance maximum

    0.25 pF

  • Diode 2-heater capacitance maximum

    0.05 pF

SECTION 3

Triode

Characteristics

  • Heater voltage

    6.3 V

  • Heater current

    230 mA

  • Typical plate voltage

    250 V

  • Transconductance

    1200 uS

  • Amplification factor

    70

  • Plate resistance

    58000 ohm

Other

  • Maximum plate voltage

    300 V

  • Maximum plate dissipation

    0.5 W

Capacitance

  • Grid-heater capacitance maximum

    0.05 pF