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

UBC81

Series-heater double-diode triode for receiver detector and audio-amplifier service. Paired diodes provide signal and control rectification while the high-mu triode supplies resistance-coupled audio gain.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
3
Base
-
Socket code
B9A
Base pins
9
Nominal heater
14 V / 100 mA

Description

Double-diode triode for detection and audio-frequency voltage amplification. The supplied French datasheet was translated to English for descriptive output.

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
-
Socket code
B9A
Base pins
9
Nominal heater voltage
14 V
Nominal heater current
100 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

3 physical sections, each with unique specifications.

Section 1

Diode

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

Published ratings and characteristics promoted from the approved source.

Section 2

Diode

X-ray radiationInterelectrode capacitances

No fixed ratings are recorded for this section.

Second physical detector diode section added in approved reconciliation.

Section 3

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
42000 Ω
Transconductance
0.00165 S
Amplification factor
70
Max plate voltage
170 V
Max plate dissipation
0.5 W
Max cathode current
5 mA

Published ratings and 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

Diode

Other

  • HeaterVoltageNominal

    14 V

    Nominal

  • HeaterCurrentNominal

    100 mA

    Nominal

  • Maximum Plate Voltage

    200 V

SECTION 3

Triode

Other

  • HeaterVoltageNominal

    14 V

    Nominal

  • HeaterCurrentNominal

    100 mA

    Nominal

  • Maximum Plate Voltage

    170 V

Characteristic

  • Transconductance

    1650 µS

    Typical

  • Amplification Factor

    70

    Typical

  • Plate Resistance

    42000 ohm

    Typical

Data set 02

1957 Philips Receiving and Amplifying Tubes

Published operating points and test conditions from this source.

SECTION 1

Diode

Application

  • Application

    Signal detection / AVC

SECTION 3

Triode

Application

  • Application

    AF amplifier

Data set 03

1958 Mullard Receiving Tubes

Published operating points and test conditions from this source.

SECTION 1

Diode

Application

  • Application

    Signal detection

SECTION 3

Triode

Application

  • Application

    AF voltage amplification

Data set 04

1963 Philips Electron Tubes Handbook V1

Published operating points and test conditions from this source.

SECTION 1

Diode

Other

  • Maximum inverse voltage

    350 V

  • Maximum average diode current

    0.8 mA

  • Maximum peak diode current

    5 mA

SECTION 3

Triode

Other

  • Plate voltage

    170 V

    TriodeSection

  • Plate current

    1.5 mA

    TriodeSection

Characteristic

  • Transconductance

    1650 uS

    TriodeSection

  • Amplification factor

    70

    TriodeSection

  • Plate resistance

    42 kohm

    TriodeSection

Data set 05

1972 Philips Receiving Tubes

Published operating points and test conditions from this source.

SECTION 1

Diode

Other

  • HeaterVoltageNominal

    14 V

    Nominal

  • HeaterCurrentNominal

    100 mA

    Nominal

  • Maximum Cathode Current

    0.8 mA

  • Maximum Peak Inverse Voltage

    350 V

  • Rectified Output Current

    0.8 mA

  • PeakForwardCurrent

    5 mA

SECTION 3

Triode

Other

  • HeaterVoltageNominal

    14 V

    Nominal

  • HeaterCurrentNominal

    100 mA

    Nominal

  • Maximum Plate Voltage

    250 V

  • Maximum Plate Dissipation

    0.5 W

  • Maximum Cathode Current

    5 mA

Characteristic

  • Transconductance

    1650 µS

    Typical

  • Amplification Factor

    70

    Typical

  • Plate Resistance

    42000 ohm

    Typical

Data set 06

1973 Mazda Valves Binder 2

Published operating points and test conditions from this source.

SECTION 1

Diode

Characteristics

  • Heater or filament voltage

    13 V

    Published nominal value

  • Heater or filament current

    100 mA

    Published nominal value

SECTION 3

Triode

Characteristics

  • Heater or filament voltage

    13 V

    Published nominal value

  • Heater or filament current

    100 mA

    Published nominal value

  • Transconductance

    1400 µS

    Published operating characteristic

Other

  • Maximum plate dissipation

    1 W

    Published maximum rating

Data set 07

1999 Philips E-Z

Published operating points and test conditions from this source.

SECTION 3

Triode

Other

  • Typical anode current

    1.5 mA

    Triode

Characteristic

  • Transconductance

    1650 µS

    Triode

  • Amplification factor

    70

    Triode