Specialized - Cathode Ray ·CathodeRay
Nineteen-inch picture tube with electrostatic focusing, magnetic deflection, and an aluminized P4 screen. Its high-voltage direct-view construction is intended for large-screen monochrome television display service.
The 19DCP4 is a 19-inch, 114-degree banded cathode-ray picture tube designed for television display applications. It features electrostatic focusing and magnetic deflection, utilizing a straight electron gun that does not require an ion trap. The screen is metal-backed (aluminized) with a P4 phosphor, providing approximately 49% center light transmittance. The physical envelope is designated as EIA J-149-F1, which incorporates a shield/rim band and a tension strap for implosion protection.
The 19DCP4 is a wide-angle picture tube with a diagonal deflection angle of 114°, a horizontal deflection angle of 102°, and a vertical deflection angle of 85°.
The screen features a metal-backed, aluminized P4 phosphor. The minimum useful projected screen dimensions are:
The 19DCP4 uses a JEDEC B7-208 base with a JEDEC 8HR basing configuration. The high-voltage anode connection is made via a JEDEC J1-21 bulb contact (recessed small cavity cap), which aligns with pin 4 within a tolerance of ±30°.
The pin connections for the JEDEC 8HR base are defined as follows:
| Pin | Connection |
|---|---|
| Pin 1 | Heater |
| Pin 2 | Grid No. 1 |
| Pin 3 | Grid No. 2 |
| Pin 4 | Grid No. 4 (Focusing Electrode) |
| Pin 6 | Grid No. 1 |
| Pin 7 | Cathode |
| Pin 8 | Heater |
| Cap | Ultor (Grid No. 3, Grid No. 5, Collector) |
| C | External Conductive Coating (must be grounded) |
The external conductive coating (C) must be connected to a reliable system ground, as it forms a capacitor with the internal anode.
The heater is designed for a nominal 6.3 V supply.
The following design-maximum ratings represent the absolute limits within which the tube must be operated. All voltages are positive with respect to the cathode unless otherwise specified.
Under typical grid-drive operating conditions, with all voltages measured positive with respect to the cathode, the operating parameters are:
These operating conditions are specified with an anode current of 100 uA on a 15 1/8" x 12" pattern (such as that generated by an RCA 2F21 Monoscope).
The 19DCP4 is an electrostatic-focus, magnetic-deflection 19-inch cathode-ray tube featuring a 114° diagonal deflection angle, a straight electron gun, and an aluminized P4 phosphor screen. Operating with a nominal 6.3 V, 600 mA heater, it provides a 172-square-inch useful screen area. The tube is designed to operate with anode voltages up to 20,000 V and utilizes a JEDEC 8HR base configuration. Proper operation requires grounding the external conductive coating and adhering to the 1.5 Megohm maximum grid-circuit resistance limit.
Small-button Neoeightar 7-contact CRT base family
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 anode and grid-2 maximum ratings are promoted from the printed ratings block; other CRT-specific focus/drive/deflection values are preserved in 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.
Typical Anode Voltage
16000 V
Phosphor
P4
Heater Voltage Nominal
6.3 V
Heater Current Nominal
600 mA
Cathode to All Other Electrodes Capacitance
5 pF
Approximate
Grid 1 to All Other Electrodes Capacitance
6 pF
Approximate