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Specialized - Cathode Ray ·CathodeRay

5X394LM

Specialized Ferranti cathode-ray display tube documented for precision visual service, with manufacturer-defined electron-optical, screen, and deflection characteristics for type 5X394LM.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
B9AD
Socket code
-
Base pins
9
Nominal heater
6.3 V / 300 mA

Description

Miniaturized rectangular airborne-radar cathode-ray tube with low-voltage electrostatic focus, magnetic deflection, and long-persistence L phosphor.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
B9AD
Socket code
-
Base pins
9
Nominal heater voltage
6.3 V
Nominal heater current
300 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

B9AD - Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

1 physical section, each with unique specifications.

Section 1

Cathode Ray

X-ray radiationInterelectrode capacitances
Max plate voltage
18000 V

Ratings, characteristics, typical operating points, and capacitances were extracted from the supplied Ferranti datasheet.

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

1963 Ferranti

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristic

  • HeaterOrFilamentVoltage

    6.3 V

  • HeaterOrFilamentCurrent

    300 mA

  • FocusingMethod

    LowVoltageElectrostatic

  • DeflectionMethod

    Magnetic

  • ScreenConstruction

    L phosphor

  • FirstAnodeVoltageForFocus

    0 to -300 V

Other

  • FinalAnodeVoltageMinimum

    8000 V

  • FinalAnodeVoltageMaximum

    18000 V

  • ThirdAnodeVoltageMinimum

    -500 V

    Negative

  • FinalAnodeVoltage

    15000 V

    ShortGridBase

  • ThirdAnodeVoltage

    -40 V

    ShortGridBase

  • FirstAnodeVoltageForFocus

    -150 V

    ShortGridBase

  • ZeroBiasBeamCurrent

    150 uA

    ShortGridBase

  • FinalAnodeVoltage

    15000 V

    HighBrightness

  • ThirdAnodeVoltage

    0 V

    HighBrightness

  • ZeroBiasBeamCurrent

    2.5 mA

    HighBrightness