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19JP4

P4 monochrome television picture tube using magnetic deflection and high-voltage direct-view operation; manufacturer documentation for 19JP4 provides focusing, deflection, and beam-control characteristics for television picture service.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
12O
Socket code
DUODECAL5
Base pins
5
Nominal heater
6.3 V / 600 mA

Description

19JP4 — Direct-View Television Picture Tube

The 19JP4 is a rectangular glass picture tube designed for direct-view television applications. It features magnetic focusing and magnetic deflection, a unipotential cathode, and an external single-field ion trap. The tube incorporates a grey filter faceplate to improve picture contrast under ambient light, providing approximately 66% light transmission at the center of the screen.

Mechanical Design and Optical Characteristics

The 19JP4 is constructed with a rectangular glass envelope. Its physical dimensions and screen area are optimized for standard television raster displays.

Physical Dimensions

  • Overall Length: 20 13/16  3/8 inches
  • Neck Diameter: 1 7/16  1/16 inches
  • Greatest Bulb Diagonal: 18 5/8  1/8 inches
  • Greatest Bulb Width: 17 1/16  1/8 inches

Screen and Optical Specifications

The screen utilizes Phosphor No. 4, which produces a white fluorescent and phosphorescent color with medium persistence. The faceplate is treated with a grey filter to enhance contrast.

  • Minimum Useful Screen Diagonal: 17 21/32 inches
  • Minimum Useful Screen Width: 16 inches
  • Minimum Useful Screen Height: 12 inches
  • Standard Raster Size: 12 inches by 16 inches

Deflection Angles

The deflection system is designed for wide-angle scanning, with approximate deflection angles of:

  • Horizontal Deflection: 65 to 66 degrees
  • Diagonal Deflection: 70 degrees

Electrical Connections and Basing

The 19JP4 uses a small shell duodecal 5-pin base (designated B5-57) with a 12D basing arrangement. High voltage to the anode is supplied via a recessed small cavity cap (J1-21) located on the bulb. This bulb contact is aligned with pin position #6 within a tolerance of  30 degrees.

Pinout Configuration (Bottom View)

The electrical connections for the duodecal base are assigned as follows:

Pin NumberConnection
Pin 1Heater
Pin 2Grid No. 1
Pin 10Grid No. 2
Pin 11Cathode
Pin 12Heater
CapAnode (Recessed small cavity cap J1-21)

Direct Interelectrode Capacitances

The approximate direct interelectrode capacitances of the tube are:

  • Cathode to all other electrodes: 5 ΙΙf
  • Grid No. 1 to all other electrodes: 6 ΙΙf

Heater and Maximum Ratings

The ratings of the 19JP4 are established under the Design Center system. Operating the tube beyond these limits may impair performance or cause permanent damage.

Heater Specifications

  • Heater Voltage: 6.3 Volts
  • Heater Current: 0.6 Ampere

Design Center Maximum Ratings

  • Maximum DC Anode Voltage: 18,000 Volts
  • Maximum DC Grid No. 2 Voltage: 410 Volts
  • Maximum Grid No. 1 Voltage:
    • DC Negative-Bias Value: 125 Volts
    • DC Positive-Bias Value: 0 Volts
    • Positive-Peak Value: 2 Volts
  • Maximum DC Peak Heater-Cathode Voltage:
    • Heater negative with respect to cathode:
      • During warm-up period (not to exceed 15 seconds): 410 Volts
      • After equipment warm-up period: 150 Volts
    • Heater positive with respect to cathode: 150 Volts

Typical Operating Conditions and Circuit Values

Under typical operating conditions, the 19JP4 is configured with specific electrode potentials and magnetic focusing parameters to achieve a focused, high-brightness display.

Typical Operating Points

  • DC Anode Voltage: 12,000 Volts
  • DC Grid No. 2 Voltage: 300 Volts
  • DC Grid No. 1 Voltage (for visual extinction of undeflected focused spot): -33 to -77 Volts

Focusing and Ion Trap Alignment

To achieve standard focus and ion separation, external magnetic components must be operated at specific currents:

  • DC Focusing Coil Current: 95  20% mA. This value is specified using a standard focus coil #109 or equivalent, positioned such that the distance from the reference line to the center of the air gap on the focus coil is 3.0 inches. This current is determined with the combined Grid No. 1 bias voltage and video signal voltage adjusted to produce a highlight brightness of 30 foot-lamberts on a 12" x 16" picture size.
  • DC Ion Trap Current: 75  50% mA, using a standard single-field coil #111.

Circuit Constraints

  • Maximum Grid No. 1 Circuit Resistance: 1.5 Megohms

Technical Summary

The 19JP4 is a rectangular glass cathode ray tube designed for direct-view television applications. It features a 12" x 16" raster size, a grey filter faceplate with 66% light transmission, and utilizes Phosphor No. 4 to produce a medium-persistence white display. Operating with a 6.3 V, 0.6 A heater, the tube supports a maximum anode voltage of 18,000 V and utilizes magnetic focusing and deflection alongside an external single-field ion trap. Its electrical interface is provided by a small shell duodecal 5-pin base and a recessed small cavity cap for the high-voltage anode connection.

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
12O
Socket code
DUODECAL5
Base pins
5
Nominal heater voltage
6.3 V
Nominal heater current
600 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

12O - 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
410 V

CRT ratings, operating conditions, capacitances, and optical/deflection data retained below 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

  • DC anode voltage

    12000 V

    Typical

Characteristic

  • Horizontal deflection angle

    65 degree

    Approximate

Capacitance

  • Cathode to all other electrodes

    5 pF

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

  • MAGNETIC FOCUS AND DEFLECTION — value 1

    12 mA

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

  • MAGNETIC FOCUS AND DEFLECTION — value 2

    16 mA

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

  • FACEPLATE LIGHT TRANSMISSION

    66 percent

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

  • HEATER

    5.3 V

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

  • HEATER POSITIVE WITH RESPECT TO CATHODE

    15 V

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

  • DC ION TRAP CURRENT STANDARD COIL #111 — value 1

    111 mA

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

  • DC ION TRAP CURRENT STANDARD COIL #111 — value 2

    75 mA

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

  • DC ION TRAP CURRENT STANDARD COIL #111 — value 3

    5 mA

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

  • 12" % 16" PICTURE SIZE. DISTANCE FROM REFERENCE LINE TO CENTER CF AIR GAP ON FOCUS — value 1

    12

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

  • 12" % 16" PICTURE SIZE. DISTANCE FROM REFERENCE LINE TO CENTER CF AIR GAP ON FOCUS — value 2

    16

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

Other

  • 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

    41 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 #1 CIRCUIT RESISTANCE — value 1

    1 mA

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

  • MAXIMUM GRID #1 CIRCUIT RESISTANCE — value 2

    1.5 mA

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