Specialized - Cathode Ray ·CathodeRay
P4 monochrome television picture tube using magnetic deflection and high-voltage direct-view operation; manufacturer documentation for 19GP4 provides focusing, deflection, and beam-control characteristics for television picture service.
The 19GP4 is a direct-view cathode ray picture tube designed primarily for television receiver applications. It features a round glass construction, a grey filter faceplate, and a unipotential cathode. The tube utilizes magnetic deflection and magnetic focus, along with an external single-field ion trap to prevent ion burn on the phosphor screen.
The 19GP4 is characterized by its round glass envelope and a specialized faceplate designed to enhance picture contrast under ambient light. The faceplate is a grey filter glass providing approximately 66% light transmission at the center. The tube produces a standard rectangular raster size of 11 3/4 inches by 15 3/4 inches.
The physical dimensions and mechanical clearances of the tube are as follows:
The screen is coated with Phosphor No. 4, which produces a white fluorescent color and a white phosphorescent color with medium persistence, making it well-suited for television display rates.
The 19GP4 uses a small shell duodecal 5-pin base (designation B5-57) with a 12D basing configuration. High-voltage anode connection is made via a recessed small cavity cap (designation J1-21) located on the side of the bulb. This anode contact is aligned with the pin position #3 within a tolerance of ± 10 degrees.
The pin connections, viewed from the bottom of the base, are assigned as follows:
| Pin Number | Connection |
|---|---|
| Pin 1 | Heater |
| Pin 2 | Grid No. 1 |
| Pin 10 | Grid No. 2 |
| Pin 11 | Cathode |
| Pin 12 | Heater |
| Anode Cap | Anode (Recessed small cavity cap J1-21) |
The direct interelectrode capacitances of the tube are relatively low, helping to maintain signal integrity:
The operating limits of the 19GP4 are defined under the Design Center rating system. Operating the tube within these limits ensures reliable performance and longevity.
For standard television operation, the typical electrical and magnetic operating parameters are established as follows:
The 19GP4 is a 66-degree magnetic deflection and magnetic focus cathode ray tube designed for television display service. Featuring a round glass bulb with an 18 7/8-inch diameter, it provides a 17 3/8-inch minimum useful screen diameter and displays an 11 3/4" x 15 3/4" raster. The tube is equipped with a grey filter faceplate offering 66% light transmission to optimize contrast, and it utilizes a standard No. 4 white phosphor. Operating at a typical anode voltage of 13,000 V (with a design maximum of 19,000 V), the 19GP4 requires an external single-field ion trap magnet and a standard focusing coil to produce a sharp, focused image. It is powered by a standard 6.3 V, 0.6 A heater and is based on a small shell duodecal 5-pin configuration.
Small-shell Duodecal 5-contact CRT base
General specifications
Properties common to every published source and operating point.
Electrical assignments shared by every tube using this base designation.
No verified pinout is recorded for this base designation.
1 physical section, each with unique specifications.
Section 1
CRT ratings, operating conditions, capacitances, and optical/deflection data retained below as parameters.
Source-dependent data
Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.
Data set 01
Published operating points and test conditions from this source.
DC anode voltage
13000 V
Typical
Deflection angle
66 degree
Approximate
Cathode to all other electrodes
5 pF
Data set 02
Published operating points and test conditions from this source.
HEATER
6.3 V
Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.
HEATER CURRENT
0.6
Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.
DC ANODE
13 V
Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.
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.
DC GRID #2 VOLTAGE — value 2
25 V
Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.
DC FOCUSING COIL CURRENT S (APPROX.)
13 mA
Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.
11 j!4" % 15 j/4^ PCI TURE SIZE. — value 1
4
Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.
11 j!4" % 15 j/4^ PCI TURE SIZE. — value 2
15
Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.
11 j!4" % 15 j/4^ PCI TURE SIZE. — value 3
4
Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.
MAXIMUMDC ANODE VOLTAGE
19 V
Published CRT datasheet value; multiple values on a row correspond to separate source-table conditions or limits.
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 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.