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Specialized - Cathode Ray ·CathodeRay

23EWP4A

Large aluminized P4 monochrome television picture tube for high-voltage direct-view service, using electrostatic focusing and magnetic deflection with manufacturer-specified operating characteristics for type 23EWP4A.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
8HR
Socket code
NEOEIGHTAR7
Base pins
-
Nominal heater
6.3 V / 450 mA

Description

23-inch direct-view monochrome television CRT with electrostatic focus, magnetic deflection, aluminized P4 screen, and gray/filter faceplate construction.

Socket description

Small-button Neoeightar 7-contact CRT base family

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
8HR
Socket code
NEOEIGHTAR7
Base pins
-
Nominal heater voltage
6.3 V
Nominal heater current
450 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

8HR - 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
22000 V
Max screen voltage
550 V

High-voltage CRT ratings promoted from source. Sylvania source includes X-ray radiation precautions/warning.

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

1950 Sylvania

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristic

  • Heater Voltage

    6.3 V

  • Heater Current

    450 mA

Other

  • Maximum Anode Voltage

    22000 V

  • Grid2 Voltage

    550 V

Data set 02

1965 Sylvania Electronic Tubes Vol3

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristics

  • Focusing method

    Electrostatic

  • Deflection method

    Magnetic

  • Horizontal deflection angle

    100 deg

  • Diagonal deflection angle

    114 deg

  • Vertical deflection angle

    83 deg

  • Fluorescence

    White

  • Persistence

    Short to medium

  • Heater voltage

    6.3 V

  • Heater current

    450 mA

Construction

  • Phosphor

    Aluminized P4

Other

  • Maximum anode voltage

    22000 V

  • Typical anode voltage

    18000 V

  • Typical focus-electrode voltage range

    -200 to +200 V

  • Typical grid2 voltage

    400 V

  • Cutoff voltage range

    -48 to -96 V

  • Grid1 circuit resistance maximum

    1.5 Mohm

  • Grid2 voltage minimum

    200 V

  • X-radiation precaution

    Operate within published maximum anode-voltage rating; source carries X-radiation warning at elevated EHT.

Capacitance

  • Grid1-to-all capacitance

    6 pF

  • External conductive coating to anode capacitance maximum

    2500 pF

Application

  • Application

    Monochrome television picture display