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Voltage Radio Detector Converter ·Pentode-Triode

5LJ8

Combined triode-pentode used as an oscillator and mixer or frequency converter in television or VHF communications receivers.

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

Description

Miniature type used as a combined oscillator and Pt ^fc-^&a ^A^-< S IA-^k/ 3p mixer in vhf television receivers. Outlines section, 0*"""^® CT lp 6B; requires 9-contact socket. Types 4LJ8 and 5LJ8 are identical with type 6LJ8 except for heater ratings. 9GF 4LJ8 5LJ8 6LJ8

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
5.6 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
5000 Ω
Transconductance
0.008 S
Amplification factor
40
Max plate voltage
280 V
Max plate dissipation
2 W
Max cathode current
20 mA

Promoted from published maximum-ratings/characteristics tables; additional source values are retained in TUBE_SECTION_PARAMETER.

Section 2

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
125000 Ω
Transconductance
0.013 S
Amplification factor
40
Max plate voltage
280 V
Max screen voltage
280 V
Max plate dissipation
2 W
Max cathode current
20 mA

Promoted from published maximum-ratings/characteristics tables; additional source values are retained in TUBE_SECTION_PARAMETER.

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

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • For use with "Flyback Transformer*' high voltage supply

    3 megohms

    Published value from supplied target entry

  • Heater Voltage (ac/dc)

    6.3 volts

    Published value from supplied target entry

  • Heater Current

    0.4 ampere

    Published value from supplied target entry

  • Heater Warm-up Time (Average)

    11 seconds

    Published value from supplied target entry

  • Plate Voltage

    280 volts

    Published value from supplied target entry

  • Grid-No

    2

    Published value from supplied target entry

  • I Supply Voltage

    280

    Published value from supplied target entry

  • Grid-No

    300

    Published value from supplied target entry

  • Cathode Current

    20 mA

    Published value from supplied target entry

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

    0 volts

    Published value from supplied target entry

  • Plate Dissipation

    2 watts

    Published value from supplied target entry

  • For grid-No

    140 volts

    Published value from supplied target entry

  • For grid-No

    300 volts

    Published value from supplied target entry

  • Plate Voltage

    125 volts

    Published value from supplied target entry

  • Grid-No

    125 volts

    Published value from supplied target entry

  • Amplification Factor

    40

    Published value from supplied target entry

  • Plate Resistance (Approx.)

    125000 ohms

    Published value from supplied target entry

  • Transconductance

    13000

    Published value from supplied target entry

  • Plate Current

    12 mA

    Published value from supplied target entry

  • Grid-No

    3.5 mA

    Published value from supplied target entry

  • Heater Current

    0.45 ampere

    Published value from supplied target entry

  • Plate Voltage

    350 volts

    Published value from supplied target entry

  • Grid-No

    330 volts

    Published value from supplied target entry

  • Plate Dissipation

    2.5 volts

    Published value from supplied target entry

  • For grid-No

    0.55 volts

    Published value from supplied target entry

  • Grid No.l Voltage

    -2 volts

    Published value from supplied target entry

Other

  • For interval of

    20 seconds

    Published value from supplied target entry

Capacitance

  • Grid to Plate

    1.8 pF

    Published value from supplied target entry

  • Grid to Cathode, Heater, Pentode Cathode, Pentode Grid No

    3

    Published value from supplied target entry

  • Plate to Cathode, Heater, Pentode Cathode, Pentode Grid No

    3

    Published value from supplied target entry

  • Plate to Cathode, Heater, Grid No

    3

    Published value from supplied target entry

  • Heater to Cathode (Each Unit)

    3.2 pF

    Published value from supplied target entry