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Voltage Triode Pentode ·Pentode-Triode

8LC8

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

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
9QY
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 amplifier applications.

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
9QY
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

9QY - 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
2 W

Published ratings and characteristics promoted where clearly stated; identical repeated diode/triode sections compressed where applicable.

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

Published ratings and characteristics promoted where clearly stated; identical repeated diode/triode sections compressed where applicable.

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

1940 RCA

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater voltage

    8.4 V

    Published nominal value

  • Heater current

    450 mA

    Published nominal value

  • Transconductance

    4000 µS

    Published operating characteristic

  • Amplification factor

    70

    Published operating characteristic

Other

  • Maximum plate dissipation

    2 W

    Published maximum or stated design maximum

  • Application

    Sync separator and gated AGC amplifier

    Television

SECTION 2

Pentode

Characteristics

  • Heater voltage

    8.4 V

    Published nominal value

  • Heater current

    450 mA

    Published nominal value

  • Transconductance

    4400 µS

    Published operating characteristic

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

    2 V

    Characteristic;PublishedValue1

  • Grid-No

    100 V

    Characteristic;PublishedValue2

  • Grid-No.l Voltage

    -2 V

    Characteristic

  • Cathode-Bias Resistor

    180 ohm

    Characteristic

  • Plate Resistance (Approx.)

    17500 ohm

    Characteristic;PublishedValue1

  • Plate Resistance (Approx.)

    100000 ohm

    Characteristic;PublishedValue2

  • Plate Current

    4 mA

    Characteristic

  • 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

  • Published value

    20 V

    Characteristic

  • 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, Pentode Grid No

    3 pF

    Capacitance;PublishedValue1

  • Grid to Cathode, Heater, Pentode Grid No

    2.8 pF

    Capacitance;PublishedValue2

  • Plate to Cathode, Heater, Pentode Grid No

    3 pF

    Capacitance;PublishedValue1

  • Plate to Cathode, Heater, Pentode Grid No

    2.2 pF

    Capacitance;PublishedValue2

  • Internal Shield

    10 pF

    Capacitance

  • Grid No

    3 pF

    Capacitance;PublishedValue1

  • Grid No

    3.4 pF

    Capacitance;PublishedValue2

  • Grid No.l to Grid No

    3 pF

    Capacitance;PublishedValue1

  • Grid No.l to Grid No

    0.36 pF

    Capacitance;PublishedValue2

  • Heater, Grid No.l, and Grid No

    2 pF

    Capacitance;PublishedValue1

  • Heater, Grid No.l, and Grid No

    12.5 pF

    Capacitance;PublishedValue2

Other

  • 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

  • Positive-bias value

    0 V

    MaximumRating

  • Negative-bias value

    100 V

    MaximumRating

  • Grid-No

    2 V

    MaximumRating;PublishedValue1

  • Grid-No

    300 V

    MaximumRating;PublishedValue2

  • Positive-bias value

    0 V

    MaximumRating

  • Negative-bias value

    50 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

  • 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