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Voltage Triode Pentode ·Pentode-Triode

8KA8

High-mu triode and sharp-cutoff pentode for television sync-separator and specialized pentode-amplifier circuits.

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

Description

High-mu triode and sharp-cutoff pentode for television sync-separator and specialized pentode amplifier circuits.

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
9PV
Socket code
B9A
Base pins
9
Nominal heater voltage
8.4 V
Nominal heater current
450 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

9PV - 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
17500 Ω
Transconductance
0.004 S
Amplification factor
70
Max plate voltage
300 V
Max plate dissipation
1.1 W

Published maximum ratings and characteristics promoted semantically from the approved source.

Section 2

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
100000 Ω
Transconductance
0.0044 S
Max plate voltage
300 V
Max screen voltage
300 V
Max plate dissipation
2 W
Max screen dissipation
1.1 W

Published maximum ratings and characteristics promoted semantically 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

1950 Sylvania

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Plate Resistance

    17500 ohm

  • Transconductance

    4000 µS

  • Amplification Factor

    70

Other

  • Maximum Plate Voltage

    300 V

  • Maximum Plate Dissipation

    1.1 W

  • Plate Voltage

    200 V

    Triode sync separator

SECTION 2

Pentode

Characteristic

  • Plate Resistance

    100000 ohm

  • Transconductance

    4400 µS

Other

  • Maximum Plate Voltage

    300 V

  • Maximum Screen Voltage

    300 V

  • Maximum Plate Dissipation

    2 W

  • Maximum Screen Dissipation

    1.1 W

  • Plate Voltage

    150 V

    Pentode AGC/noise inverter

  • Screen Voltage

    100 V

    Pentode section

Data set 02

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Heater Warm-up Time (Average)

    11 s

    Characteristic;PublishedValue1

  • Heater Warm-up Time (Average)

    11 s

    Characteristic;PublishedValue2

  • Peak value

    200 V

    Characteristic;PublishedValue1

  • Peak value

    200 V

    Characteristic;PublishedValue2

  • Average value

    100 V

    Characteristic;PublishedValue1

  • Average value

    100 V

    Characteristic;PublishedValue2

  • Plate Supply Voltage

    200 V

    Characteristic;PublishedValue1

  • Plate Supply Voltage

    150 V

    Characteristic;PublishedValue2

  • Grid-No

    3 V

    Characteristic;PublishedValue1

  • Grid-No

    0 V

    Characteristic;PublishedValue2

  • Grid-No

    2 V

    Characteristic;PublishedValue1

  • Grid-No

    100 V

    Characteristic;PublishedValue2

  • Grid-No.l Supply Voltage —

    2 V

    Characteristic;PublishedValue1

  • Grid-No.l Supply Voltage —

    0 V

    Characteristic;PublishedValue2

  • Plate Resistance (Approx.)

    17500 ohm

    Characteristic;PublishedValue1

  • Plate Resistance (Approx.)

    100000 ohm

    Characteristic;PublishedValue2

  • Plate Current

    4 mA

    Characteristic;PublishedValue1

  • Plate Current

    4 mA

    Characteristic;PublishedValue2

  • Grid-No

    2 mA

    Characteristic;PublishedValue1

  • Grid-No

    2.8 mA

    Characteristic;PublishedValue2

  • For plate current of

    10 V

    Characteristic;PublishedValue1

  • For plate current of

    -5 V

    Characteristic;PublishedValue2

  • For plate current of

    20 V

    Characteristic;PublishedValue1

  • For plate current of

    -4 V

    Characteristic;PublishedValue2

  • Published value

    20 V

    Characteristic;PublishedValue1

  • Published value

    -7 V

    Characteristic;PublishedValue2

  • Plate Resistance

    17500 ohm

    Section1

  • Transconductance

    4000 uS

    Section1

  • Amplification Factor

    70

    Section1

Capacitance

  • Grid to Plate

    2.2 pF

    Capacitance

  • Grid to Cathode, Heater, and Internal Shield

    2.8 pF

    Capacitance

  • Plate to Cathode, Heater, and Internal Shield

    2.2 pF

    Capacitance

  • Grid No.l to Plate

    0.1 pF

    Capacitance

  • and Internal Shield

    9.5 pF

    Capacitance

  • Grid No.l to Grid No

    3 pF

    Capacitance;PublishedValue1

  • Grid No.l to Grid No

    0.5 pF

    Capacitance;PublishedValue2

  • Grid No

    3 pF

    Capacitance;PublishedValue1

  • Grid No

    2.2 pF

    Capacitance;PublishedValue2

  • Grid No

    3 pF

    Capacitance;PublishedValue1

  • Grid No

    7 pF

    Capacitance;PublishedValue2

Other

  • Plate Voltage

    300 V

    MaximumRating

  • Positive-bias value

    0 V

    MaximumRating

  • Negative-bias value

    50 V

    MaximumRating

  • Plate Dissipation

    1.1 W

    MaximumRating

  • For fixed-bias operation

    0.25 megohm

    MaximumCircuitValue

  • For cathode-bias operation

    1 megohm

    MaximumCircuitValue

  • DC Plate Voltage

    300 V

    MaximumRating

  • Peak Positive-Pulse Plate Voltage#

    600 V

    MaximumRating

  • Negative-bias value —

    1000 V

    MaximumRating

  • Grid-No

    2 V

    MaximumRating;PublishedValue1

  • Grid-No

    300 V

    MaximumRating;PublishedValue2

  • Negative-bias value —

    500 V

    MaximumRating

  • Plate Dissipation

    2 W

    MaximumRating

  • For grid-No

    2 V

    MaximumRating;PublishedValue1

  • For grid-No

    150 V

    MaximumRating;PublishedValue2

  • For grid-No

    1.1 V

    MaximumRating;PublishedValue3

  • For grid-No

    2 V

    MaximumRating;PublishedValue1

  • For grid-No

    150 V

    MaximumRating;PublishedValue2

  • For grid-No

    300 V

    MaximumRating;PublishedValue3

  • For grid-No

    300 V

    MaximumRating;PublishedValue4

  • Grid-No

    3 megohm

    MaximumCircuitValue;PublishedValue1

  • Grid-No

    0.68 megohm

    MaximumCircuitValue;PublishedValue2

  • For fixed-bias operation

    0.5 megohm

    MaximumCircuitValue

  • Maximum Plate Voltage

    300 V

    Section1

  • Maximum Plate Dissipation

    1.1 W

    Section1

SECTION 2

Pentode

Other

  • Maximum Plate Voltage

    300 V

    Section2

  • Maximum Screen Voltage

    300 V

    Section2

  • Maximum Plate Dissipation

    2 W

    Section2

Characteristic

  • Plate Resistance

    100000 ohm

    Section2

  • Transconductance

    4400 uS

    Section2