19CLP4 — Direct-View Picture Tube

The 19CLP4 is a 19-inch direct-view rectangular glass cathode-ray tube designed for television display applications. It features a spherical faceplate made of gray filter glass, an aluminized screen, and a low Grid #1 voltage design optimized for cathode drive. The tube utilizes a 92-degree magnetic deflection angle, electrostatic focusing, and an external conductive coating. It does not require an ion trap.

Construction and Mechanical Specifications

The 19CLP4 is constructed with a J149B1 (or equivalent) glass bulb envelope and a B6-203 base. The faceplate is spherical and composed of gray filter glass with approximately 78% light transmittance at the center. The screen is aluminized and uses a P4 phosphor.

Physical Dimensions

• Overall Length: 15-1/4 +/- 3/8 inches
• Neck Length: 5-1/2 +/- 3/16 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 Dimensions (Minimum Useful Projected)

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

The bulb contact is a J1-21 recessed small cavity cap, which aligns with pin position #6 within +/- 30 degrees.

Electrical Characteristics and Ratings

The 19CLP4 operates with a nominal heater voltage of 6.3 V and a heater current of 600 +/- 10% mA. The heater warm-up time is 11 seconds.

Direct Interelectrode Capacitances

• Cathode to all other electrodes: approximately 5 pF
• Grid #1 to all other electrodes: approximately 6 pF
• External conductive coating to anode: 1,500 min. to 2,000 max. pF

Deflection Angles (Approximate)

• Diagonal: 92 degrees
• Horizontal: 80 degrees
• Vertical: 65 degrees

Design Maximum Ratings

All voltages are positive and measured with respect to Grid #1 unless otherwise specified.

• Anode Voltage: 12,000 V (min.) to 19,800 V (max.)
• Grid #4 (Focusing Electrode) Voltage: -500 V to +1100 V
• Grid #2 Voltage: 25 V (min.) to 40 V (max.)
• Cathode Voltage: 100 V (max.)
• Heater Voltage: 5.8 V (min.) to 7.0 V (max.)
• Maximum Heater-Cathode Voltage:
  • Heater negative with respect to cathode:
    • During warm-up period (<= 15 seconds): -410 V
    • After equipment warm-up period: -180 V
  • Heater positive with respect to cathode: 180 V
• Grid #1 Circuit Resistance: 1.5 M-ohms (max.)

Typical Operating Conditions (Cathode Drive Service)

In typical cathode drive service, voltages are positive and measured with respect to Grid #1 unless otherwise specified:

• Anode Voltage: 14,500 V
• Grid #4 (Focusing Electrode) Voltage: 250 V (with individual tubes focusing anywhere between 0 and 500 V)
• Grid #2 Voltage: 35 V (for visual extinction of a focused raster)
• Cathode Voltage: 25 to 40 V (with combined Grid #1 bias and video-signal voltage adjusted for 150 microamperes anode current on a 15-1/8 x 12 inch pattern from a 2F21 Monoscope or equivalent)

Pinout and Basing

The 19CLP4 uses the 12L basing arrangement with a B6-203 base. The pin connections are as follows:

Technical Summary

The 19CLP4 is a rectangular, direct-view television picture tube featuring a 19-inch diagonal spherical faceplate with gray filter glass and an aluminized P4 phosphor screen. It utilizes electrostatic focusing and 92-degree magnetic deflection. The tube is designed for cathode drive service with a low Grid #1 voltage (35 V typical) and does not require an ion trap. It operates with a 6.3 V, 600 mA heater and is housed in a J149B1 bulb with a B6-203 base and 12L pinout.