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Specialized - Cathode Ray ·CathodeRay

19CKP4

Nineteen-inch direct-view monochrome television picture tube with electrostatic focusing, 114-degree magnetic deflection, an aluminized screen, external conductive coating, and a non-ion-trap low-grid-2 cathode-drive gun. It belongs to the high-voltage picture-tube family designed for bright receiver display.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
8HR
Socket code
DUODECAL5
Base pins
-
Nominal heater
6.3 V / 600 mA

Description

19CKP4 — Electrostatic-Focus Magnetic-Deflection Picture Tube

The 19CKP4 is a 19-inch glass picture tube designed for use in television receivers. It features electrostatic focusing and magnetic deflection, with a short overall length and a small neck diameter. The tube incorporates a non-ion trap gun designed specifically for low Grid No. 2 voltage operation in cathode-drive circuits. It is equipped with an aluminized screen and an external conductive coating that acts as a filter capacitor when grounded.

Mechanical Specifications and Envelope

The 19CKP4 utilizes a J149-A1 glass bulb with a spherical gray glass faceplate, which provides an approximate light transmittance of 78% at the center.

Physical Dimensions

  • Overall Length: 11 3/4 ± 1/4 inches
  • Neck Length: 4 1/2 ± 1/8 inches
  • Greatest Diagonal: 18 5/8 ± 1/8 inches
  • Greatest Width: 16 13/32 ± 1/8 inches
  • Greatest Height: 13 11/32 ± 1/8 inches

Screen Characteristics and Deflection Angles

The minimum useful projected screen dimensions are:

  • Diagonal: 17 9/16 inches
  • Horizontal: 15 1/8 inches
  • Vertical: 12 inches
  • Total Area: 172 square inches

The approximate deflection angles are:

  • Diagonal: 114°
  • Horizontal: 102°
  • Vertical: 87°

Electrical Characteristics and Interelectrode Capacitances

The 19CKP4 has a nominal heater voltage of 6.3 V and a heater current of 600 ± 30 mA. The heater warm-up time is approximately 11 seconds.

Direct Interelectrode Capacitances

  • Cathode to all other electrodes: approximately 5 µµf
  • Grid No. 1 to all other electrodes: approximately 6 µµf
  • External conductive coating to Anode: 1,000 µµf minimum / 1,500 µµf maximum

Pinout and Basing Diagram

The tube uses the 8HR basing configuration with a JEDEC No. B7-237 or B7-208 base. The anode connection is made via a JEDEC No. J1-21 bulb contact, which aligns with Pin No. 4 within ±30 degrees.

The pin connections are as follows:

  • Pin 1: Heater (H)
  • Pin 2: Grid No. 1 (G1)
  • Pin 3: Grid No. 2 (G2)
  • Pin 4: Focus Electrode / Grid No. 4 (F)
  • Pin 6: Grid No. 1 (G1)
  • Pin 7: Cathode (K)
  • Pin 8: Heater (H)
  • Bulb Contact: Anode (A)

Design-Maximum Ratings

The following design-maximum ratings are specified. All voltages are positive and measured with respect to the cathode unless otherwise noted:

  • Anode Voltage: 15,000 V minimum / 22,000 V maximum
  • Grid No. 4 (Focusing Electrode) Voltage: -500 V to +1,000 V maximum
  • Grid No. 2 Voltage: 40 V minimum / 100 V maximum
  • Grid No. 1 Voltage:
    • Maximum Negative DC Value: 140 V
    • Maximum Negative Peak Value: 200 V
    • Maximum Positive DC Value: 0 V
    • Maximum Positive Peak Value: 2 V
  • Heater Voltage: 5.7 V minimum / 6.9 V maximum
  • Maximum Heater-Cathode Voltage:
    • Heater negative to cathode (during warm-up ≤ 15 seconds): 410 V
    • Heater negative to cathode (after warm-up): 300 V
    • Heater positive to cathode: 180 V

Typical Operating Conditions (Cathode-Drive Service)

Under typical operating conditions in cathode-drive service, the tube is configured with the following parameters:

  • Anode Voltage: 18,000 V DC
  • Grid No. 4 Voltage (Focusing Electrode): 250 V DC (individual tubes focus within a range of 0 to 500 V DC)
  • Grid No. 2 Voltage: 50 V DC
  • Cathode-to-Grid No. 1 Voltage: 31 to 49 V DC (required for visual extinction of the focused raster)

Maximum Circuit Values

To ensure safe and reliable operation, the following circuit resistance limits must be observed:

  • Maximum Grid No. 1 Circuit Resistance: 1.5 megohms
  • Minimum Grid No. 2 Circuit Resistance: 0.1 megohms
  • Minimum Focusing Electrode Circuit Resistance: 0.1 megohms

Note: It is advisable to include protective resistance in the Grid No. 2 and focusing electrode circuits; a common resistor may be utilized for this purpose.

Technical Summary

The 19CKP4 is a 19-inch, 114-degree magnetic-deflection glass picture tube featuring electrostatic focusing and an aluminized screen. Designed specifically for cathode-drive television receivers, it operates with a low Grid No. 2 voltage (typically 50 V) and does not require an ion trap. Its physical design features a short overall length of 11 3/4 inches and a small neck diameter, making it suitable for compact receiver designs. The tube operates with a nominal 6.3 V heater and is rated for anode voltages up to 22,000 V.

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
8HR
Socket code
DUODECAL5
Base pins
-
Nominal heater voltage
6.3 V
Nominal heater current
600 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

No fixed ratings are recorded for this section.

CRT specialized anode, grid, optical, and deflection data retained in TUBE_SECTION_PARAMETER.

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

1968 General Electric Co

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Other

  • Maximum Anode Voltage

    22000 V

  • Heater Warmup Time

    11 s

  • Minimum Anode Voltage

    15000 V

  • Maximum Grid2 Voltage

    100 V

  • Minimum Grid2 Voltage

    40 V

  • Typical Anode Voltage

    18000 V

  • Typical Focus Grid Voltage

    250 V

  • Typical Grid2 Voltage

    50 V

  • Cathode To Grid1 Voltage

    31 to 49 V

    CathodeDriveService

Characteristic

  • Horizontal Deflection Angle

    102 degree

  • Vertical Deflection Angle

    87 degree

  • Diagonal Deflection Angle

    114 degree

Capacitance

  • Cathode To All Other Electrodes Capacitance

    5 pF

  • Grid1 To All Other Electrodes Capacitance

    6 pF

  • External Coating To Anode Capacitance

    1000 to 1500 pF