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Specialized - Cathode Ray ·CathodeRay

19FLP4

Wide-angle aluminized P4 monochrome television picture tube using electrostatic focusing and magnetic deflection, designed for high-voltage direct-view service with a large approximately 19-inch screen.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
-
Base pins
7
Nominal heater
6.3 V / 450 mA

Description

19FLP4 Picture Tube

The 19FLP4 is a specialized cathode-ray picture tube designed with PAN-O-PLY integral implosion protection, low-voltage electrostatic focusing, and a wide-angle 114-degree magnetic deflection system. It features an advanced electron gun design that operates efficiently without requiring an external ion-trap magnet.

Optical and Mechanical Design

The 19FLP4 utilizes an aluminized P4-Sulfide phosphor screen behind a filterglass faceplate. This faceplate provides approximately 48% light transmission at its center, enhancing contrast under ambient lighting conditions.

Mechanically, the tube has a weight of approximately 15 pounds. Its physical envelope is designated as a J149 FA bulb, which is terminated with a Small-Button Neoeightar 7-pin base (JEDEC No. B7-208, Arrangement 1) and a Recessed Small Cavity cap (JEDEC No. J1-21) for the high-voltage anode connection. The tube also features a Regular-Band external conductive coating, which requires a grounding contact near the reference line.

Physical Dimensions and Screen Area

  • Overall Length: 11.625 ± 0.250 inches
  • Neck Length: 4.375 ± 0.125 inches
  • Overall Height: 13.500 ± 0.125 inches
  • Projected Screen Area: 172 square inches
  • Minimum Screen Dimensions:
    • Diagonal: 17.562 inches
    • Width: 15.187 inches
    • Height: 12.000 inches
  • Minimum Rim-Band Opening Dimensions:
    • Diagonal: 18.285 inches
    • Width: 15.950 inches
    • Height: 12.840 inches

Electrical Characteristics and Pinout

The 19FLP4 is designed with a 7-pin base configuration designated as the 8HR bottom view. The pinout connections are assigned as follows:

Pin / CapConnection
Pin 1Heater
Pin 2Grid No. 1
Pin 3Grid No. 2
Pin 4Grid No. 4 (Focusing Electrode)
Pin 6Grid No. 1
Pin 7Cathode
Pin 8Heater
CapAnode (Grid No. 3, Grid No. 5, Screen, Collector)
C (Coating)External Conductive Coating

The external conductive coating and the implosion protection hardware must be reliably connected to system ground.

Heater Ratings

The heater is designed for a nominal voltage of 6.3 V, with an allowable operating range of 5.7 V minimum to 6.9 V maximum. Under nominal conditions, the heater current is 450 ± 20 mA. The average heater warm-up time is 11 seconds.

Calculation of Nominal Heater Power: Using the nominal voltage and current: Power=6.3 V×0.450 A=2.835 W\text{Power} = 6.3\text{ V} \times 0.450\text{ A} = 2.835\text{ W}

Interelectrode Capacitances

  • Cathode to all other electrodes: 5 pF
  • Grid No. 1 to all other electrodes: 6 pF
  • External coating to anode: 1250 pF minimum to 1750 pF maximum

Operating Conditions and Drive Service

The 19FLP4 is typically operated in Cathode-Drive Service, where operating voltages are specified as positive with respect to Grid No. 1.

Typical Operating Conditions

Under typical cathode-drive conditions, the operating parameters are established as follows:

  • Anode Voltage: 16,000 V
  • Grid-No. 4 (Focusing) Voltage: 200 V (with an optimum focus range of 0 to +400 V under specified conditions of 100 µA anode current on a 10.5" x 14" raster pattern)
  • Grid-No. 2 Voltage: 300 V
  • Cathode Voltage (for raster cutoff): 28 to 62 V

Design-Maximum Ratings

The design-maximum ratings define the absolute limits within which the tube must be operated to ensure reliability and longevity. All voltages are positive with respect to the cathode unless otherwise specified:

  • Anode Voltage: 11,000 V minimum to 23,000 V maximum
  • Grid-No. 4 (Focusing) Voltage: Positive 1,100 V maximum; Negative 550 V maximum
  • Grid-No. 2 Voltage: 200 V minimum to 550 V maximum
  • Grid-No. 1 Voltage:
    • Negative peak: 220 V maximum
    • Negative bias: 155 V maximum
    • Positive bias: 0 V maximum
    • Positive peak: 2 V maximum
  • Peak Heater-Cathode Voltage:
    • Heater negative to cathode during warm-up (<= 15 seconds): 450 V maximum
    • Heater negative to cathode after warm-up: 300 V maximum
    • Heater positive to cathode (combined AC & DC): 200 V maximum
    • Heater positive to cathode (DC component only): 100 V maximum
  • Maximum Grid-No. 1 Circuit Resistance: 1.5 MΩ

Deflection and Scanning Geometry

The 19FLP4 utilizes magnetic deflection to sweep the electron beam across the wide-angle screen. The deflection angles are:

  • Diagonal Deflection Angle: 114°
  • Horizontal Deflection Angle: 102°
  • Vertical Deflection Angle: 85°

The combination of a 114-degree deflection angle and a short neck length of 4.375 inches enables a highly compact cabinet depth for television receivers utilizing this tube.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
7
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
23000 V

Cathode-ray electron-gun/screen system; anode/ultor maximum promoted to MaxPlateVoltage when explicitly published. No explicit X-ray precaution detected 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

    450 mA

    Nominal heater current

  • Phosphor

    P4

    Published phosphor designation

  • /'1 External conductive coating to anodes

    1250 to 1750 pF

    /'1 External conductive coating to anodes. 1250 min — 1750 max pF

  • Projected Area of Screen

    172 sq in

    Projected Area of Screen 172 sq in

  • Anode Voltage

    1000 to -23000 V

    Anode Voltage 1 1000 min-23000 max V

  • Grid-No.2 Voltage

    200 to 550 V

    Grid-No.2 Voltage 200 min— 550 max V

  • Heater Voltage

    5.7 to -6.9 V

    Heater Voltage 5.7 min-6.9 max V

  • During equipment warm-up period

    450 V

    During equipment warm-up period 5 i5 seconds 450 max V

  • After equipment warm-up period

    300 V

    After equipment warm-up period 300 max V

  • Combined AC & DC voltage

    200 V

    Combined AC & DC voltage 200 max V

  • Anode Voltage

    16000 V

    Anode Voltage 16000 V

  • Grid-No.4 Voltageb

    200 V

    Grid-No.4 Voltageb 200 V

  • Grid-No.2 Voltage

    300 V

    Grid-No.2 Voltage 300 V

  • Cathode Voltage

    28 to 62 V

    Cathode Voltage 28 to 62 V

Construction

  • Focusing Method

    Electrostatic

    Published focusing method

  • Deflection Method

    Magnetic

    Published deflection method

Characteristic

  • LOW-VOLTAGE ELECTROSTATIC FOCUS

    14 deg

    LOW-VOLTAGE ELECTROSTATIC FOCUS 1 14° MAGNETIC DEFLECTION

Capacitance

  • Cathode to all other electrodes

    5 pF

    Cathode to all other electrodes. 5 pF

  • Grid No.1 to all other electrodes

    6 pF

    Grid No.1 to all other electrodes. 6 pF

  • Heater Current at

    20 mA

    Heater Current at 6.3 V 450 ± 20 mA