Skip to main content
Tube Tinker — Electron Tube Database
Alternatives & variationsDownload PDF datasheet

Specialized - Cathode Ray ·CathodeRay

23EAP4

Twenty-three-inch direct-view monochrome television picture tube with electrostatic focusing, magnetic deflection, and high-voltage operation. Manufacturer data documents its large-screen receiver-display construction, optical characteristics, and picture-tube operating limits.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
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
-
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

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

Published Sylvania television-CRT ratings, focus/grid conditions, heater-cathode limits, capacitances, and typical operating points retained where legible.

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

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

    99 deg

  • Diagonal deflection angle

    110 deg

  • Vertical deflection angle

    82 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

    16000 V

  • Typical focus-electrode voltage maximum

    400 V

  • Typical grid2 voltage

    300 V

  • Cutoff voltage range

    -35 to -72 V

  • Grid1 circuit resistance maximum

    1.5 Mohm

  • Focus-electrode voltage minimum

    -550 V

  • Focus-electrode voltage maximum

    1100 V

  • Grid2 voltage maximum

    550 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