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

UBC41

Series-heater double-diode high-mu triode combining receiver detection, AVC generation, and audio voltage amplification. Two diodes provide signal and control rectification while the triode supplies subsequent gain.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
3
Base
-
Socket code
B8A
Base pins
8
Nominal heater
14 V / 100 mA

Description

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

Socket description

Rimlock 8-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B8A
Base pins
8
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

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
45000 Ω
Transconductance
0.0017 S
Amplification factor
75
Max plate voltage
170 V
Max plate dissipation
0.5 W

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

1951 Mullard Valve and Service Manual

Published operating points and test conditions from this source.

SECTION 3

Triode

Other

  • Plate Voltage

    170 V

    TriodeSection

  • Plate Current

    1.5 mA

    TriodeSection

Characteristic

  • Transconductance

    1650 µS

    TriodeSection

  • Amplification Factor

    70

    TriodeSection

  • Plate Resistance

    42000 ohm

    TriodeSection

Data set 02

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

    1700 µS

    Typical

  • Amplification Factor

    75

    Typical

  • Plate Resistance

    45000 ohm

    Typical

Data set 03

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 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

1967 Mullard Receiving Tubes for Maintenance

Published operating points and test conditions from this source.

SECTION 1

Diode

Other

  • Ih

    100 mA

    Published in approved UBC41.pdf target datasheet; Section2

  • Ca " d-h <

    0.05 pF

    Published in approved UBC41.pdf target datasheet; Section2

Capacitance

  • Ca /d - gt <

    0.007 pF

    Published in approved UBC41.pdf target datasheet; Section2

  • Ca" d - g t <

    0.03 pF

    Published in approved UBC41.pdf target datasheet; Section2

  • Ca d --a t <

    0.01 pF

    Published in approved UBC41.pdf target datasheet; Section2

  • Cg_ k

    2.75 pF

    Published in approved UBC41.pdf target datasheet; Section2

  • Ca- k

    1.5 pF

    Published in approved UBC41.pdf target datasheet; Section2

  • Ca - g

    1.3 pF

    Published in approved UBC41.pdf target datasheet; Section2

  • Cit -II <

    0.05 pF

    Published in approved UBC41.pdf target datasheet; Section2

  • I

    0.8 pF

    Published in approved UBC41.pdf target datasheet; Section2

  • Ca " d - k

    0.7 pF

    Published in approved UBC41.pdf target datasheet; Section2

  • Ca ' d- a " ct <

    0.3 pF

    Published in approved UBC41.pdf target datasheet; Section2

  • Ca ' d - h <

    0.1 pF

    Published in approved UBC41.pdf target datasheet; Section2

SECTION 3

Triode

Other

  • Ih

    100 mA

    Published in approved UBC41.pdf target datasheet; Section1

  • Ca " d-h <

    0.05 pF

    Published in approved UBC41.pdf target datasheet; Section1

Capacitance

  • Ca /d - gt <

    0.007 pF

    Published in approved UBC41.pdf target datasheet; Section1

  • Ca" d - g t <

    0.03 pF

    Published in approved UBC41.pdf target datasheet; Section1

  • Ca d --a t <

    0.01 pF

    Published in approved UBC41.pdf target datasheet; Section1

  • Cg_ k

    2.75 pF

    Published in approved UBC41.pdf target datasheet; Section1

  • Ca- k

    1.5 pF

    Published in approved UBC41.pdf target datasheet; Section1

  • Ca - g

    1.3 pF

    Published in approved UBC41.pdf target datasheet; Section1

  • Cit -II <

    0.05 pF

    Published in approved UBC41.pdf target datasheet; Section1

  • I

    0.8 pF

    Published in approved UBC41.pdf target datasheet; Section1

  • Ca " d - k

    0.7 pF

    Published in approved UBC41.pdf target datasheet; Section1

  • Ca ' d- a " ct <

    0.3 pF

    Published in approved UBC41.pdf target datasheet; Section1

  • Ca ' d - h <

    0.1 pF

    Published in approved UBC41.pdf target datasheet; Section1