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Voltage Radio Detector Converter ·Pentode-Triode

4GX7

Triode plus frame-grid pentode designed for television frequency-converter service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
-
Socket code
B9A
Base pins
9
Nominal heater
4.2 V / 600 mA

Description

The Westinghouse 4GX7 is a triode plus frame-grid pentode converter for VHF oscillator-mixer service.

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
4.2 V
Nominal heater current
600 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
4700 Ω
Transconductance
0.0085 S
Amplification factor
40
Max plate voltage
275 V
Max plate dissipation
1.5 W
Max cathode current
20 mA

Published source ratings and characteristics promoted where applicable; additional electrical and operating data retained as parameters.

Section 2

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
200000 Ω
Transconductance
0.011 S
Max plate voltage
275 V
Max screen voltage
275 V
Max plate dissipation
2.2 W
Max screen dissipation
0.45 W
Max cathode current
20 mA

Published source ratings and characteristics promoted where applicable; additional electrical and operating data retained as parameters.

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

1964 RMA EIA

Published operating points and test conditions from this source.

SECTION 1

Triode

Capacitance

  • Triode grid-plate capacitance

    1.2 pF

  • Triode input capacitance

    2.3 pF

  • Triode output capacitance

    1.9 pF

Other

  • Triode typical plate voltage

    125 V

  • Triode grid voltage

    -1 V

  • Triode plate current

    13 mA

Characteristics

  • Triode cutoff voltage

    -6 V

Application

  • Application

    VHF oscillator

SECTION 2

Pentode

Capacitance

  • Pentode grid1-plate capacitance

    0.005 pF

  • Pentode input capacitance

    5.4 pF

  • Pentode output capacitance

    3.3 pF

  • Pentode grid1-grid2 capacitance

    1.6 pF

Other

  • Pentode typical plate voltage

    125 V

  • Pentode typical screen voltage

    125 V

  • Pentode grid1 voltage

    -1 V

  • Pentode plate current

    8 mA

  • Pentode screen current

    2.5 mA

Characteristics

  • Pentode cutoff voltage

    -2.5 V

Application

  • Application

    VHF mixer / amplifier

Data set 02

1965 Westinghouse Data Book

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater Voltage

    4.2 V

  • Heater Current

    600 mA

  • Grid-Plate Capacitance

    0.005 pF

    PublishedDirectInterelectrodeCapacitance

Other

  • Maximum Plate Voltage

    275 V

SECTION 2

Pentode

Other

  • Maximum Plate Voltage

    275 V

  • Maximum Plate Dissipation

    2.2 W

  • Maximum Screen Supply Voltage

    275 V

  • Maximum Screen Dissipation

    0.45 W

Characteristics

  • Transconductance

    11000 uS

    RepresentativePublishedPoint

  • Grid-Plate Capacitance

    0.005 pF

  • Input Capacitance

    5.4 pF

  • Output Capacitance

    3.3 pF