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

21ATP4

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
12L
Socket code
DUODECAL5
Base pins
6
Nominal heater
6.3 V / 600 mA

Description

54 cm monochrome television picture tube with electrostatic focusing, magnetic deflection and aluminized screen.

Socket description

Small-shell Duodecal 5-contact CRT base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
12L
Socket code
DUODECAL5
Base pins
6
Nominal heater voltage
6.3 V
Nominal heater current
600 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

12L - 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
Max screen voltage
500 V

Published ratings and characteristics promoted where clearly stated; identical repeated sections compressed where applicable.

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 grid 2 voltage

    500 V

  • Typical grid 2 voltage

    500 V

    Typical operating conditions

Characteristic

  • Diagonal deflection angle

    90 deg

Capacitance

  • Cathode to all other electrodes

    773 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 VOLTAGE

    6.3 V

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

  • HEATER POSITIVE WITH RESPECT TO CATHODE

    1 V

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

  • ION TRAP MAGNET FIELD STRENGTH (APPRO%.)

    35 mA

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

  • CURRENT OF 100 NILROANP EKES OX A 19 1/8" X 15" PICTURE SIZE. — value 1

    1

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

  • CURRENT OF 100 NILROANP EKES OX A 19 1/8" X 15" PICTURE SIZE. — value 2

    8

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

  • CURRENT OF 100 NILROANP EKES OX A 19 1/8" X 15" PICTURE SIZE. — value 3

    15

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

Other

  • MAXIMUM DC ANODE, GRID #3, GRID #5 VOLTAGE ' — value 1

    3 V

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

  • MAXIMUM DC ANODE, GRID #3, GRID #5 VOLTAGE ' — value 2

    5 V

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

  • MAXIMUM DC ANODE, GRID #3, GRID #5 VOLTAGE ' — value 3

    1 V

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

  • MAXIMUM DC GRID #4 VOLTAGE (FOCUSING ELECTRODE) -5OO TO }1000 — 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 (FOCUSING ELECTRODE) -5OO TO }1000 — value 2

    -5 V

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

  • MAXIMUM DC GRID #4 VOLTAGE (FOCUSING ELECTRODE) -5OO TO }1000 — value 3

    1000 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 #i CIRCUIT RESISTANCE

    1.5 mA

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

Data set 03

1968 General Electric Co

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Other

  • Typical Anode Voltage

    16000 V

  • Typical Grid No. 2 Voltage

    300 V

  • Grid No. 1 Maximum Negative Bias

    125 V

  • Grid No. 1 Maximum Positive Peak

    2 V

Data set 04

1968 Mazda Belvu

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristics

  • Heater or filament voltage

    6.3 V

    Published nominal value

  • Heater or filament current

    600 mA

    Published nominal value

  • Screen diagonal

    54 cm

    Published

  • Deflection angle

    90 deg

    Published