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Specialized - Cathode Ray ·CathodeRay

21AMP4B

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
12N
Socket code
-
Base pins
5
Nominal heater
6.3 V / 600 mA

Description

21AMP4B is a monochrome cathode-ray picture tube for television/display service. The supplied RCA data describes magnetic focusing and magnetic deflection, with a P4 phosphor screen and a published maximum anode/ultor voltage of 20000 V.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
12N
Socket code
-
Base pins
5
Nominal heater voltage
6.3 V
Nominal heater current
600 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

12N - 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
20000 V

Cathode-ray electron-gun/screen system; anode/ultor maximum promoted to MaxPlateVoltage when explicitly published. Explicit X-ray warning/precaution or X-radiation characteristic is present in the supplied source.

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

1971 RCA HB3 Binder 1 of 7

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Other

  • Heater Voltage

    6.3 V

    Nominal heater voltage

  • Heater Current

    600 mA

    Nominal heater current

  • Phosphor

    P4

    Published phosphor designation

  • Heater Current at

    600 mA

    Heater Current at 6.3 volts 600 ma

  • External conductive coating to anode (

    2500 pF

    External conductive coating to anode ( 2500 max. pf

  • Anode Voltage

    20000 V

    Anode Voltage 20000 max. volts

  • Grid-No.2 Voltage

    550 V

    Grid-No.2 Voltage 550 max. volts

  • After equipment warm-up period

    200 V

    After equipment warm-up period 200 max. volts

  • respect to cathode

    200 V

    respect to cathode 200 max. volts

  • With anode voltage of i6000 volts

    0 V

    With anode voltage of i6000 volts

  • and grid—No.z voltage o,f

    30 V

    and grid—No.z voltage o,f 30o volts

  • extinction of focused raster

    -28 to -72 V

    extinction of focused raster -28 to -72 volts

  • Grid-No.l-Circuit Resistance

    1.5 MΩ

    Grid-No.l-Circuit Resistance 1.5 max. megohms

Construction

  • Focusing Method

    Magnetic

    Published focusing method

  • Deflection Method

    Magnetic

    Published deflection method

Characteristic

  • MAGNETIC FOCUS

    90 deg

    MAGNETIC FOCUS 90° MAGNETIC DEFLECTION

Capacitance

  • Grid No.l to all other electrodes

    6 pF

    Grid No.l to all other electrodes 6 pf

  • Cathode to all other electrodes

    5 pF

    Cathode to all other electrodes 5 pf

  • Projected Area of Screen

    262 sq in

    Projected Area of Screen 262 sq. in.