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Tube Tinker — Electron Tube Database
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Specialized - Cathode Ray ·CathodeRay

31B81

Flat-screen all-electrostatic cathode-ray tube with post-deflection acceleration for high-precision instruments. The accelerated beam and electrostatic deflection system provide a bright, accurately positioned trace for precision oscillographic measurement.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
-
Base pins
14
Nominal heater
6.3 V / 500 mA

Description

Flat-screen all-electrostatic cathode-ray tube with post-deflection acceleration for high-precision instruments.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
14
Nominal heater voltage
6.3 V
Nominal heater current
500 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

1 physical section, each with unique specifications.

Section 0

Cathode Ray

X-ray radiationInterelectrode capacitances
Max plate voltage
8000 V

All-electrostatic CRT; additional electrode limits are 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

1960 Mazda

Published operating points and test conditions from this source.

SECTION 0

Cathode Ray

Other

  • MinimumFinalAnodeVoltage

    2 kV

  • MaximumThirdAnodeVoltage

    4 kV

  • MinimumThirdAnodeVoltage

    1 kV

  • MaximumSecondAnodeVoltage

    2 kV

  • Maximum Heater Cathode Voltage

    150 V

Data set 02

1961 AEI Industrial Valves

Published operating points and test conditions from this source.

SECTION 0

Cathode Ray

Other

  • MaximumFinalAnodeVoltage

    8000 V

  • MinimumFinalAnodeVoltage

    2000 V

  • MaximumThirdAnodeVoltage

    4000 V

  • MinimumThirdAnodeVoltage

    1000 V

  • MaximumSecondAnodeVoltage

    2000 V

  • MaximumFirstAnodeVoltage

    2500 V

  • MinimumFirstAnodeVoltage

    1000 V

  • Maximum Heater Cathode Voltage

    150 V

Characteristic

  • TypicalSecondAnodeVoltage

    350 V

Capacitance

  • Cathode To All Capacitance

    8 pF

  • GridToAllCapacitance

    17 pF

  • X1ToX2Capacitance

    2.5 pF

  • Y1ToY2Capacitance

    3 pF

Data set 03

1961 Associated Electrical Industries

Published operating points and test conditions from this source.

SECTION 0

Cathode Ray

Other

  • MaximumFinalAnodeVoltage

    8000 V

  • MinimumFinalAnodeVoltage

    2000 V

  • MaximumThirdAnodeVoltage

    4000 V

  • MinimumThirdAnodeVoltage

    1000 V

  • MaximumSecondAnodeVoltage

    2000 V

  • MaximumFirstAnodeVoltage

    2500 V

  • MinimumFirstAnodeVoltage

    1000 V

  • Maximum Heater Cathode Voltage

    150 V

Characteristic

  • TypicalSecondAnodeVoltage

    350 V

Capacitance

  • Cathode To All Capacitance

    8 pF

  • GridToAllCapacitance

    17 pF

  • X1ToX2Capacitance

    2.5 pF

  • Y1ToY2Capacitance

    3 pF