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19ERP4

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
DUODECAL5
Base pins
-
Nominal heater
6.3 V / 600 mA

Description

19ERP4 — Television Picture Tube

The 19ERP4 is a television picture tube designed with low-voltage electrostatic focus and magnetic deflection. It features a wide-angle deflection system, an aluminized screen, and integrated implosion protection. The tube does not require an ion trap.

Physical and Mechanical Specifications

The 19ERP4 is constructed using a spherical gray filter glass envelope with a light transmittance of approximately 49% at the center. The screen utilizes an aluminized P4 phosphor. Implosion protection is provided by a tension band system (banded implosion protection).

Envelope and Screen Dimensions

The physical dimensions of the tube are highly specified to ensure proper mounting and alignment:

  • Over-all Length: 11.375" ± 0.250"
  • Neck Length: 4.125" ± 0.125"
  • Neck Diameter: Maximum of 1.168" at the splice
  • Greatest Dimensions:
    • Diagonal: 18.733" ± 0.100"
    • Width: 16.552" ± 0.100"
    • Height: 13.446" ± 0.100"
  • Minimum Useful Screen Dimensions (Projected):
    • Diagonal: 17.563"
    • Horizontal Axis: 15.125"
    • Vertical Axis: 12"
    • Total Area: 172 square inches
  • Net Weight: 15 lbs.

Bulb and Base Designations

The tube utilizes the EIA J149F1 bulb configuration. The anode connection is made via an EIA J1-21 bulb contact (JEDEC No. J1-21). The base is an EIA B7-208 (Small Button 7-Pin Base, JEDEC No. B7-208) with an EIA 8HR basing arrangement.

Mechanical Alignment and Installation Notes

  • Base Pin Alignment: Base pin 4 aligns with the major axis of the tube within 30° and is positioned on the same side as the anode terminal.
  • Yoke Reference Line: The reference line is determined by JEDEC Reference Line Gauge No. 126 positioned on the funnel. Any permanent magnet (PM) centering magnet (rated 0 to 8 gauss) should extend no more than 2.125" from this reference line.
  • Tension Band: The tension band must be grounded.
  • Insulating Coating: A transparent insulating coating 3" in diameter is present on the bulb. This area must be cleaned only with a soft, dry, lintless cloth.

Electrical Connections and Pinout

The 19ERP4 uses an 8HR basing configuration. The pin assignments are as follows:

Pin NumberConnection
Pin 1Heater (H)
Pin 2Grid No. 1 (G1)
Pin 3Grid No. 2 (G2)
Pin 4Grid No. 4 (G4 - Focusing Electrode)
Pin 6Grid No. 1 (G1)
Pin 7Cathode (K)
Pin 8Heater (H)
CapAnode (A)

Heater Ratings

The heater is designed for a nominal voltage of 6.3 V and a current of 600 ± 5% mA. The heater warm-up time is 11 seconds. This warm-up time is defined as the time required to reach 80% of the rated heater voltage when 4 times the rated heater voltage is applied to a circuit consisting of the heater in series with a resistance equal to 3 times the rated voltage divided by the rated current.

Interelectrode Capacitances

  • Cathode to All Other Electrodes: Approximately 5 pF
  • Grid No. 1 to All Other Electrodes: Approximately 6 pF
  • External Conductive Coating to Anode: Minimum 1250 pF, Maximum 1750 pF. This external coating must be grounded, as it forms a supplementary filter capacitance for the high-voltage supply.

Insulation Resistance

The electrical resistance between the external conductive coating and the implosion protection hardware must be a minimum of 5 Megohms.

Design-Maximum Ratings

The following ratings are established under the Design-Maximum System. All voltages are positive and measured with respect to Grid No. 1 unless otherwise specified.

ParameterRating Value
Maximum Anode Voltage23,000 V
Minimum Anode Voltage11,000 V
Maximum Grid No. 4 (Focusing Electrode) Voltage+1100 V to -550 V
Maximum Grid No. 2 Voltage550 V
Minimum Grid No. 2 Voltage200 V
Maximum Grid No. 1 Negative Bias Value154 V
Maximum Grid No. 1 Negative Peak Value220 V
Maximum Grid No. 1 Positive Bias Value0 V
Maximum Grid No. 1 Positive Peak Value2 V

Heater-Cathode Voltage Limits

To prevent breakdown between the heater and cathode, the following voltage limits must be observed:

  • Heater Negative with Respect to Cathode (During Warm-up, ≤ 15 seconds): Maximum 450 V
  • Heater Negative with Respect to Cathode (After Warm-up): Maximum 300 V
  • Heater Positive with Respect to Cathode: Maximum 200 V

Operating Characteristics and Typical Conditions

Typical Cathode Drive Operation

In typical cathode drive service, voltages are specified positive with respect to Grid No. 1:

  • Anode Voltage: 20,000 V. Note: Operation above 16 kV may require shielding to limit soft X-ray radiation.
  • Grid No. 4 (Focusing Electrode) Voltage: 200 V. Individual tubes are designed to achieve satisfactory focus between 0 and 400 V under specified focus conditions.
  • Grid No. 2 Voltage: 400 V. A voltage of not less than 300 V is recommended, as lower voltages can adversely affect resolution.
  • Cathode Voltage for Raster Cutoff: 36 to 78 V.

Focus Condition Measurement

The focus condition is measured with the cathode bias and video-signal adjusted to produce an anode current of 150 µA on a 12" x 15.125" pattern. This pattern is generated from a type 2F21 monoscope or an equivalent source.

Deflection Angles

The tube is designed for wide-angle magnetic deflection, with approximate deflection angles of:

  • Diagonal: 114°
  • Horizontal: 102°
  • Vertical: 86°

Limiting Circuit Values

To protect the tube from damage due to internal arcing or excessive current, the following circuit resistance limits must be maintained:

  • Maximum Grid No. 1 Circuit Resistance: 1.5 Megohms
  • Minimum Grid No. 2 & Grid No. 4 Circuit Resistance: 10,000 Ohms (protective resistance is advisable).

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
-
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

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.

Television CRT electron-gun/display section.

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 Westinghouse Data Book

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristics

  • Heater Voltage

    6.3 V

  • Heater Current

    600 mA

  • Heater Warm-up Time

    11 s

  • Focusing Method

    Low Voltage Electrostatic text

  • Deflection Method

    Magnetic text

  • Horizontal Deflection Angle

    102 deg

    Approximate

  • Vertical Deflection Angle

    86 deg

    Approximate

  • Diagonal Deflection Angle

    114 deg

    Approximate

  • Phosphor

    Aluminized P4 text

  • Fluorescence

    White text

  • Persistence

    Short to Medium text

  • Light Transmittance

    49 percent

    Approximate

  • Cathode-to-All Capacitance

    5 pF

    Approximate

  • Grid1-to-All Capacitance

    6 pF

    Approximate

  • External Coating-to-Anode Capacitance Minimum

    1750 pF

  • External Coating-to-Anode Capacitance Maximum

    2250 pF

Other

  • Maximum Anode Voltage

    23000 V

  • Minimum Anode Voltage

    11000 V

  • Maximum Focus Electrode Voltage Positive

    1100 V

    Grid4

  • Maximum Focus Electrode Voltage Negative

    -550 V

    Grid4

  • Maximum Grid2 Voltage

    550 V

  • Minimum Grid2 Voltage

    200 V

  • Maximum Heater-Cathode Voltage During Warmup

    450 V

    Duration<=15s

  • Maximum Heater-Cathode Voltage After Warmup

    300 V

  • Typical Anode Voltage

    20000 V

    CathodeDrive

  • Typical Focus Voltage Minimum

    0 V

    Grid4

  • Typical Focus Voltage Maximum

    400 V

    Grid4

  • Typical Grid2 Voltage

    400 V

    CathodeDrive

  • Cathode Voltage for Raster Cutoff Minimum

    36 V

    CathodeDrive

  • Cathode Voltage for Raster Cutoff Maximum

    78 V

    CathodeDrive

  • Maximum Grid1 Circuit Resistance

    1.5 Mohm