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Voltage Pentode or Tetrode (with diode) ·Diode-Diode-Pentode

6LT8

Television diode-pentode combining IF amplification with video detection, allowing the pentode to provide wideband gain while the diode recovers the detected picture signal.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
3
Base
9RL
Socket code
B9A
Base pins
9
Nominal heater
6.3 V / 600 mA

Description

Twin diode and sharp-cutoff pentode for television horizontal oscillator and AFC discriminator circuits. Explicit heater variant/co-designation of 8LT8 in the approved source.

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
9RL
Socket code
B9A
Base pins
9
Nominal heater voltage
6.3 V
Nominal heater current
600 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

9RL - Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

3 physical sections, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
200000 Ω
Transconductance
0.013 S
Max plate voltage
330 V
Max screen voltage
330 V
Max plate dissipation
3.1 W
Max screen dissipation
0.65 W

Sharp-cutoff pentode unit used as Class A amplifier/horizontal oscillator.

Section 2

Diode

X-ray radiationInterelectrode capacitances
Max cathode current
5 mA

Diode unit 1; continuous plate-current maximum 5 mA.

Section 3

Diode

X-ray radiationInterelectrode capacitances
Max cathode current
5 mA

Diode unit 2; continuous plate-current maximum 5 mA.

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

1968 General Electric Co

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Maximum Plate Voltage

    330 V

  • Maximum Screen Voltage

    330 V

  • Maximum Plate Dissipation

    3.1 W

  • Maximum Screen Dissipation

    0.65 W

Characteristic

  • Plate Resistance

    200000 ohm

  • Transconductance

    13000 uS

  • Interelectrode Capacitances Published

    true

SECTION 2

Diode

Other

  • Maximum Cathode Current

    5 mA

Characteristic

  • Average Diode Current

    20 mA

    5 V DC applied

  • Interelectrode Capacitances Published

    true

SECTION 3

Diode

Other

  • Maximum Cathode Current

    5 mA

Characteristic

  • Average Diode Current

    20 mA

    5 V DC applied

  • Interelectrode Capacitances Published

    true

Data set 02

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Heater Warm-up Time (Average)

    11 s

    Other;PublishedValue1

  • Heater Warm-up Time (Average)

    11 s

    Other;PublishedValue2

  • Heater Warm-up Time (Average)

    11 s

    Other;PublishedValue3

  • Peak value

    200 V

    Other;PublishedValue1

  • Peak value

    200 V

    Other;PublishedValue2

  • Peak value

    200 V

    Other;PublishedValue3

  • Average value

    100 V

    Other;PublishedValue1

  • Average value

    100 V

    Other;PublishedValue2

  • Average value

    100 V

    Other;PublishedValue3

  • Plate Voltage

    330 V

    MaximumRating

  • Grid-No

    2 V

    MaximumRating;PublishedValue1

  • Grid-No

    330 V

    MaximumRating;PublishedValue2

  • Grid-No.l (Control-Grid) Voltage, Positive-bias value

    0 V

    MaximumRating

  • Plate Dissipation

    3.1 W

    MaximumRating

  • For grid-No

    2 V

    MaximumRating;PublishedValue1

  • For grid-No

    165 V

    MaximumRating;PublishedValue2

  • For grid-No

    0.65 V

    MaximumRating;PublishedValue3

  • For grid-No

    2 V

    MaximumRating;PublishedValue1

  • For grid-No

    165 V

    MaximumRating;PublishedValue2

  • For grid-No

    33 V

    MaximumRating;PublishedValue3

  • For grid-No

    300 V

    MaximumRating;PublishedValue4

  • Maximum Plate Voltage

    330 V

    Section1

  • Maximum Screen Voltage

    330 V

    Section1

  • Maximum Plate Dissipation

    3.1 W

    Section1

  • Maximum Screen Dissipation

    0.65 W

    Section1

Characteristic

  • Plate Voltage

    125 V

    Characteristic

  • Grid-No

    2 V

    Characteristic;PublishedValue1

  • Grid-No

    125 V

    Characteristic;PublishedValue2

  • Cathode-Bias Resistor

    56 ohm

    Characteristic

  • Plate Resistance (Approx.)

    200000 ohm

    Characteristic

  • Plate Current

    10 mA

    Characteristic

  • Grid-No

    2 mA

    Characteristic;PublishedValue1

  • Grid-No

    3.4 mA

    Characteristic;PublishedValue2

  • Grid-No.l Voltage (Approx.) for plate current of

    20 V

    Characteristic;PublishedValue1

  • Grid-No.l Voltage (Approx.) for plate current of

    -3.5 V

    Characteristic;PublishedValue2

  • Tube Voltage Drop for plate current of

    20 mA

    Characteristic

  • Plate Resistance

    200000 ohm

    Section1

  • Transconductance

    13000 uS

    Section1

SECTION 3

Diode

Characteristic

  • Tube Voltage Drop at 20 mA

    5 V

    InstantaneousValue