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Voltage - Triode (single) ·Triode

B409

Early directly heated four-volt receiving triode for battery-operated amplifier service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B4
Base pins
4
Nominal heater
4 V / 150 mA

Description

B409 is listed in the supplied tube table as a triode. Published electrical values were transcribed from its target row.

Socket description

European 4-pin base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B4
Base pins
4
Nominal heater voltage
4 V
Nominal heater current
150 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

1 physical section, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
5000 Ω
Transconductance
0.0018 S
Amplification factor
9
Max plate voltage
250 V
Max plate dissipation
3 W
Max cathode current
15 mA

Published table ratings and electrical characteristics reviewed; ambiguous cells were not inferred.

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

1938 Philips Miniwatt Vacuum Tube Catalog

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Maximum plate voltage

    250 V

    Published table rating

  • Plate voltage

    250 V

    Published operating point

  • Control-grid bias

    18 V

    Published operating point

  • Plate current

    12 mA

    Published operating point

  • Power output

    3 W

    Published operating point

Characteristic

  • Plate resistance

    5000 ohm

    Published table characteristic

  • Transconductance

    12000 µS

    Published table characteristic

  • Amplification factor

    9

    Published table characteristic

  • Heater/filament voltage

    4 V

    Published heater/filament rating

  • Heater/filament current

    150 mA

    Published heater/filament rating

Data set 02

1999 Philips 0-D

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Typical anode voltage

    250 V

    Published datasheet value

  • Normal anode current

    12 mA

    Published datasheet value

  • Grid bias

    -18 V

    Published datasheet value

  • Typical output power

    0.51 W

    ClassA; Va=250V; Ra=10kΩ

Characteristics

  • Maximum transconductance

    - to 2 mA/V

    Published datasheet value

  • Normal transconductance

    1.8 mA/V

    Published datasheet value

  • Internal resistance

    5000 Ω

    Published datasheet value

  • Maximum grid-circuit resistance

    - to 1.5 MΩ

    Published datasheet value

  • Interelectrode capacitance 1

    5.2 pF

    Published datasheet value

  • Interelectrode capacitance 2

    3.1 pF

    Published datasheet value

  • Interelectrode capacitance 3

    4.6 pF

    Published datasheet value