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Power - Pentode Single (NOT beam) (under 10W) ·Pentode

8448

High-reliability mobile-radio power pentode developed as a rugged replacement for the 12BY7A.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B9A
Base pins
9
Nominal heater
13.5 V / 260 mA

Description

Reliable mobile-radio power pentode intended as a high-reliability replacement for the 12BY7A.

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
13.5 V
Nominal heater current
260 mA
Parallel heater voltage
6.75 V
Parallel heater current
380 mA
Series capable
Yes

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

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
93000 Ω
Transconductance
0.011 S
Amplification factor
28.5
Max plate voltage
330 V
Max screen voltage
190 V
Max plate dissipation
6.5 W
Max screen dissipation
1.2 W

Power pentode; triode-connected amplification factor is retained.

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

Pentode

Other

  • Heater voltage

    13.5 V

    Nominal

  • Heater current

    260 mA

    Nominal

  • Plate voltage

    330 V

    Published operating table; OperatingPoint1

  • Plate voltage

    250 V

    Published operating table; OperatingPoint1

  • Screen voltage

    180 V

    Published operating table; OperatingPoint1

Characteristic

  • Plate current

    26 mA

    Published operating table; OperatingPoint1

  • Transconductance

    11000 uS

    Published operating table; OperatingPoint1

  • Plate resistance

    93000 ohm

    Published operating table; OperatingPoint1

Data set 02

1966 Tung Sol Electronic Tubes 4 of 4

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Heater voltage series

    13.5 V

  • Heater current series

    190 mA

  • Heater voltage parallel

    6.75 V

  • Heater current parallel

    380 mA

  • Maximum plate voltage

    330 V

  • Maximum screen voltage

    190 V

  • Maximum plate dissipation

    6.5 W

  • Maximum screen dissipation

    1.2 W

  • Plate voltage

    250 V

    AverageCharacteristics

  • Screen voltage

    180 V

    AverageCharacteristics

  • Cathode bias resistor

    100 ohm

    AverageCharacteristics

  • Plate current

    26 mA

    AverageCharacteristics

  • Screen current

    5.7 mA

    AverageCharacteristics

Characteristic

  • Transconductance

    11000 uS

    AverageCharacteristics

  • Plate resistance

    93000 ohm

    AverageCharacteristics

  • Triode amplification factor

    28.5

    TriodeConnection