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

21ASP4

Twenty-one-inch direct-view monochrome television picture tube designed for large-screen receiver service. Manufacturer data documents its magnetic scanning system, high-voltage operation, and picture-tube optical and electrical characteristics.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
B12D
Base pins
5
Nominal heater
6.3 V / 600 mA

Description

Direct-view cathode-ray picture tube for television display service. Electrical ratings, operating conditions, capacitances, optical data, and construction details were extracted from the supplied datasheet.

Socket description

Duodecar 12-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B12D
Base pins
5
Nominal heater voltage
6.3 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

1 physical section, each with unique specifications.

Section 1

Cathode Ray

X-ray radiationInterelectrode capacitances
Max plate voltage
1 V
Max screen voltage
5 V

CRT ratings, operating conditions, capacitances, optical and deflection 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

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Other

  • Heater voltage

    6.3 V

    Nominal

  • Heater current

    600 mA

    Nominal

  • Maximum anode voltage

    18000 V

  • Maximum grid 2 voltage

    500 V

  • Typical anode voltage

    18000 V

    Typical operating conditions

  • Typical grid 2 voltage

    500 V

    Typical operating conditions

Characteristic

  • Diagonal deflection angle

    70 deg

Capacitance

  • Cathode to all other electrodes

    5 pF

    Approximate

  • Grid 1 to all other electrodes

    6 pF

    Approximate

Data set 02

1966 Tung Sol Electronic Tubes 4 of 4

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristics

  • HEATER

    6.3 V

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

  • DC ANODE VOLTAGE

    16 V

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

  • DC GRID #2 VOLTAGE — value 1

    2 V

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

  • DC GRID #2 VOLTAGE — value 2

    3 V

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

  • DC GR 10 #1 VOLTAGE S — value 1

    1 V

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

  • DC GR 10 #1 VOLTAGE S — value 2

    -2 V

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

  • DC GR 10 #1 VOLTAGE S — value 3

    -72 V

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

  • DC ION — value 1

    30 mA

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

  • DC ION — value 2

    1 mA

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

  • DC ION — value 3

    40 mA

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

  • DC ION TRAP MAGNET RATED STRENGTH

    35 mA

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

Other

  • MAXIMUM DC ANODE VOLTAGE

    1 V

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

  • MAXIMUM DC GRID #4 VOLTAGE — value 1

    4 V

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

  • MAXIMUM DC GRID #4 VOLTAGE — value 2

    -5 V

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

  • MAXIMUM DC GRID @2 VOLTAGE — value 1

    2 V

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

  • MAXIMUM DC GRID @2 VOLTAGE — value 2

    5 V

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

  • MAXIMUM GRID #1 VOLTAGE

    1 V

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.

  • MAXIMUM GRID #i CIRCUIT RESISTANCE

    1.5 mA

    Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.