Specialized - Cathode Ray ·CathodeRay
Direct-view cathode-ray picture tube documented by manufacturer data for type 16JP4A; available extracted technical detail is limited, so the description remains conservative.
The 16JP4A is a round glass, direct-view cathode ray picture tube designed primarily for television display applications. It is identical to the 16JP4 except for its grey filter faceplate, which is designed to enhance contrast under ambient room lighting.
The 16JP4A features a round glass bulb construction with an external conductive coating. Its physical dimensions and mechanical specifications include:
The 12N basing arrangement provides the following connections, viewed from the bottom of the base:
| Pin | Connection |
|---|---|
| Pin 1 | Heater |
| Pin 2 | Grid No. 1 |
| Pin 10 | Grid No. 2 |
| Pin 11 | Cathode |
| Pin 12 | Heater |
| Cap | Anode |
The 16JP4A utilizes a sulfide-type phosphor designated as No. 4. Its optical properties include:
The operating limits of the 16JP4A are specified under the Design Center rating system. Operating the tube beyond these limits may impair performance or cause permanent damage.
| Parameter | Rating (Design Center Value) |
|---|---|
| Heater Voltage | 6.3 V |
| Heater Current | 0.6 A |
| Maximum DC Anode Voltage | 14,000 V |
| Maximum DC Grid No. 2 Voltage | 410 V |
| Maximum DC Grid No. 1 Negative-Bias Value | 125 V |
| Maximum DC Grid No. 1 Positive-Bias Value | 0 V |
| Maximum Grid No. 1 Positive-Peak Value | 2 V |
| Maximum Grid No. 1 Circuit Resistance | 1.5 MΩ |
The maximum peak voltage between the heater and the cathode is restricted to prevent insulation breakdown:
Under typical operating conditions in a television receiver, the tube is operated with the following parameters:
The direct interelectrode capacitances of the tube are approximately:
The external conductive coating forms a capacitor with the internal anode, which can be utilized in the receiver's high-voltage filtering circuit.
The 16JP4A is a 16-inch round glass cathode ray tube designed for television display applications. It features magnetic focus and deflection with a 60-degree deflection angle, a unipotential cathode, and a sulfide-based No. 4 white phosphor screen. The 16JP4A is distinguished from the standard 16JP4 by its grey filter faceplate, which has a nominal light transmission of 66% at the center. Operating with a 6.3 V, 0.6 A heater, the tube is rated for a maximum DC anode voltage of 14,000 V (typically operated at 11,000 V) and requires an external double-field ion trap and focusing coil. It utilizes a small shell duodecal 5-pin base with a 12N basing configuration and a J1-21 recessed cavity cap for the high-voltage anode connection.
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-specific anode/focus/deflection ratings retained as parameters rather than mapped to ordinary plate/screen fields.
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.
Maximum Anode Voltage
14000 V
Typical Anode Voltage
11000 V
Maximum Grid2 Voltage
410 V
Typical Grid2 Voltage
250 V
DeflectionAngleApproximate
60 degree
FocusingMethod
Magnetic
DeflectingMethod
Magnetic
PhosphorNumber
4
FluorescentColor
White
Persistence
Medium
Data set 02
Published operating points and test conditions from this source.
MAGNETIC FOCUS 8 DEFLECTION
8 mA
Published CRT datasheet value; multiple values on a row represent the source table's separate conditions/limits.
DEFLECTION
6 degrees
Published CRT datasheet value; multiple values on a row represent the source table's separate conditions/limits.
DC ANODE
11000 V
Published CRT datasheet value; multiple values on a row represent the source table's separate conditions/limits.
DC GRID #2 VOLTAGE — value 1
2 V
Published CRT datasheet value; multiple values on a row represent the source table's separate conditions/limits.
DC GRID #2 VOLTAGE — value 2
250 V
Published CRT datasheet value; multiple values on a row represent the source table's separate conditions/limits.
DC FOCUSING COIL CURRENT (APPROX.j
115 mA
Published CRT datasheet value; multiple values on a row represent the source table's separate conditions/limits.
DC ION TRAP CURRENT STANDARD CULL #108 (APPROX.) — value 1
108 mA
Published CRT datasheet value; multiple values on a row represent the source table's separate conditions/limits.
DC ION TRAP CURRENT STANDARD CULL #108 (APPROX.) — value 2
120 mA
Published CRT datasheet value; multiple values on a row represent the source table's separate conditions/limits.
MAXIMUM DC GRID #2 VOLTAGE — value 1
2 V
Published CRT datasheet value; multiple values on a row represent the source table's separate conditions/limits.
MAXIMUM DC GRID #2 VOLTAGE — value 2
41 V
Published CRT datasheet value; multiple values on a row represent the source table's separate conditions/limits.
MAXIMUM GRID #1 VOLTAGE
1 V
Published CRT datasheet value; multiple values on a row represent the source table's separate conditions/limits.
MAXIMUM GRID #1 CIRCUIT RESISTANCE
1 mA
Published CRT datasheet value; multiple values on a row represent the source table's separate conditions/limits.