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Voltage Triode Pentode ·Pentode-Triode

8489

Reliable medium-mu triode plus sharp-cutoff pentode combination for amplifier and control service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
-
Socket code
B9A
Base pins
9
Nominal heater
6.3 V / 450 mA

Description

Medium-mu triode plus sharp-cutoff pentode combination for reliable amplifier and control service.

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
6.3 V
Nominal heater current
450 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

2 physical sections, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
4700 Ω
Transconductance
0.0045 S
Amplification factor
21
Max plate voltage
330 V
Max plate dissipation
2.8 W

Medium-mu triode section.

Section 2

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
170000 Ω
Transconductance
0.007 S
Max plate voltage
330 V
Max screen voltage
330 V
Max plate dissipation
2.3 W
Max screen dissipation
0.55 W

Sharp-cutoff pentode section.

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

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater voltage

    6.3 V

    Nominal

  • Heater current

    450 mA

    Nominal

  • Plate voltage

    330 V

    Published operating table; OperatingPoint1

  • Plate voltage

    330 V

    Published operating table; OperatingPoint2

  • Plate voltage

    150 V

    Published operating table; OperatingPoint1

  • Plate voltage

    125 V

    Published operating table; OperatingPoint2

Characteristic

  • Plate current

    15 mA

    Published operating table; OperatingPoint1

  • Plate current

    12 mA

    Published operating table; OperatingPoint2

  • Transconductance

    4500 uS

    Published operating table; OperatingPoint1

  • Transconductance

    7000 uS

    Published operating table; OperatingPoint2

  • Plate resistance

    4700 ohm

    Published operating table; OperatingPoint1

  • Plate resistance

    170000 ohm

    Published operating table; OperatingPoint2

SECTION 2

Pentode

Other

  • Heater voltage

    6.3 V

    Nominal

  • Heater current

    450 mA

    Nominal

  • Plate voltage

    330 V

    Published operating table; OperatingPoint1

  • Plate voltage

    330 V

    Published operating table; OperatingPoint2

  • Plate voltage

    150 V

    Published operating table; OperatingPoint1

  • Plate voltage

    125 V

    Published operating table; OperatingPoint2

Characteristic

  • Plate current

    15 mA

    Published operating table; OperatingPoint1

  • Plate current

    12 mA

    Published operating table; OperatingPoint2

  • Transconductance

    4500 uS

    Published operating table; OperatingPoint1

  • Transconductance

    7000 uS

    Published operating table; OperatingPoint2

  • Plate resistance

    4700 ohm

    Published operating table; OperatingPoint1

  • Plate resistance

    170000 ohm

    Published operating table; OperatingPoint2

Data set 02

1966 Tung Sol Electronic Tubes 4 of 4

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate voltage

    150 V

    Triode

  • Grid voltage

    -3 V

    Triode

  • Plate current

    15 mA

    Triode

Characteristic

  • Transconductance

    4500 uS

    Triode

  • Plate resistance

    4700 ohm

    Triode

  • Amplification factor

    21

    Triode

Capacitance

  • Triode-grid to pentode-plate capacitance

    0.02 pF

    Coupling

  • Pentode-grid to triode-plate capacitance

    0.02 pF

    Coupling

  • Pentode-plate to triode-plate capacitance

    0.15 pF

    Coupling

SECTION 2

Pentode

Other

  • Plate voltage

    125 V

    Pentode

  • Grid voltage

    -1 V

    Pentode

  • Plate current

    12 mA

    Pentode

  • Screen voltage

    125 V

    Pentode

  • Screen current

    3.8 mA

    Pentode

Characteristic

  • Transconductance

    7000 uS

    Pentode

  • Plate resistance

    170000 ohm

    Pentode