10ANP16 — Special Purpose Cathode Ray Tube
The 10ANP16 is a special-purpose, 10-inch round glass cathode ray tube (CRT) designed for applications requiring magnetic deflection and magnetic focus. It features a spherical, gray-glass faceplate, an aluminized screen, a 7/8-inch diameter neck, and a miniature base. The "10ANP16" designation specifically utilizes the P16 phosphor, which provides violet fluorescence with extremely short persistence, making it suitable for specialized high-speed or rapid-decay display systems.
Phosphor Characteristics and Screen Protection
The 10ANP16 is distinguished by its P16 phosphor screen. The screen is aluminized and deposited on a gray, spherical glass faceplate to enhance contrast and brightness. The characteristics of the P16 phosphor, along with other options in the 10ANP series, are detailed below:
Due to the physical properties of the P16 phosphor (as well as the P19 and P25 phosphors), the screen is highly susceptible to permanent damage if the electron beam current density is allowed to rise too high. To prevent burning of the phosphor, operation must be restricted to minimum beam current densities.
Mechanical Specifications and Base Connections
The 10ANP16 features a 10-inch round glass bulb with a spherical faceplate. It has a maximum overall length of 16 inches and a minimum useful screen diameter of 9 inches. The neck of the tube has a nominal diameter of 7/8 inch (specifically 0.840 inch with a tolerance of +0.056 / -0.030 inch).
Physical Dimensions and Alignment
- Bulb Diameter: 10-1/2 ± 1/16 inches
- Minimum Useful Screen Diameter: 9 inches
- Maximum Overall Length: 16 inches
- Deflection Angle (Approximate): 50 degrees
- Bulb Contact: J1-21 recessed small cavity cap
- Base: E9-37 miniature base
- Basing Configuration: 9NB
The J1-21 anode cap is aligned such that its plane passes halfway between Pin 1 and Pin 9 with an alignment tolerance of ±10 degrees. The cap is located on the same side of the envelope as Pins 1 and 9. The reference line of the tube is determined by the point where the leading edge of a JEDEC G-112 reference line gauge (a cylinder 2 inches long with an internal diameter of 1.500 +0.003 / -0.000 inches) stops.
Pinout Configuration (9NB Basing)
The 9NB base connection scheme, viewed from the bottom of the tube, is as follows:
- Pin 1: Grid No. 1
- Pin 2: Heater
- Pin 3: Grid No. 2
- Pin 4: No Connection
- Pin 5: Cathode
- Pin 6: Grid No. 2
- Pin 7: No Connection
- Pin 8: Heater
- Pin 9: Grid No. 1
- Anode Cap (J1-21): Anode
A socket with a center opening must be used to clear the tubulation (which has a maximum diameter of 1/4 inch). Extreme care must be taken when handling the tube to avoid damaging the exposed tubulation and bending the base pins.
Electrical and Interelectrode Capacitance Data
The 10ANP16 operates with an indirectly heated cathode. The heater requires a nominal 6.3 V supply and draws a low current of 300 mA, which is highly efficient for a CRT of this size.
Maximum Ratings (Design Maximum Values)
The operating limits of the 10ANP16 must be strictly observed to prevent premature failure or degradation. The design maximum ratings are:
- Anode Voltage: 12,000 Volts dc
- Grid No. 2 Voltage: 450 Volts dc
- Grid No. 1 Voltage:
- Negative Bias Value: 200 Volts dc
- Positive Bias Value: 0 Volts dc
- Positive Peak Value: 0 Volts dc
- Peak Heater-Cathode Voltage:
- Heater Negative with Respect to Cathode: 180 Volts
- Heater Positive with Respect to Cathode: 180 Volts
- Grid No. 1 Circuit Resistance: 1.5 Megohms Max.
X-Ray Radiation Warning
When operating the 10ANP16, X-ray radiation shielding may be necessary to protect personnel from prolonged exposure at close range. This precaution is particularly critical if the tube is operated at voltages higher than the manufacturer's maximum rated anode voltage of 12,000 V dc or 16,000 volts, whichever is less (meaning shielding is recommended when approaching or exceeding the 12,000 V dc limit).
Typical Operating Conditions
Under typical operating conditions, the 10ANP16 is set up with the following parameters:
- Anode Voltage: 9,000 Volts dc
- Grid No. 2 Voltage: 250 Volts dc
- Grid No. 1 Voltage (for visual extinction of undeflected focused spot): -15 to -45 Volts dc
- Focusing Coil Current (Approximate): 40 to 60 mA dc
- Linewidth: 0.013 Inch Max.
- Spot Position (Undeflected): Within a 1/2-inch radius circle
- Modulation: 40 Volts Max.
Operating Notes and Performance Considerations
- Accelerator Voltage Limits: While the typical anode voltage is 9,000 V dc, the accelerator voltage should generally not be operated below 7,000 V dc. Operating below this threshold results in a significant decrease in both display brilliance and spot definition.
- Focusing Coil Specifications: The typical focusing coil current of 40 to 60 mA dc is measured at an accelerator (anode) current of 100 µA. This measurement is taken with the center of the air gap of a JEDEC Focus Coil No. 127 (or equivalent) positioned exactly 2-1/2 inches from the reference line, with the tube properly shielded.
- Linewidth and Modulation: The maximum linewidth of 0.013 inch and the maximum modulation voltage of 40 volts are measured in accordance with the MIL-E-1 specification at an anode current of 400 µA.
- Undeflected Spot Position: When the tube is properly shielded, the center of the undeflected, focused spot will fall within a circle of 1/2-inch radius concentric with the physical center of the tube face.
Technical Summary
The 10ANP16 is a specialized 10-inch round glass cathode ray tube utilizing magnetic deflection (50-degree deflection angle) and magnetic focus. It is equipped with a highly efficient 6.3 V, 300 mA heater, a miniature E9-37 base (9NB basing), and a J1-21 anode contact. Its defining feature is the P16 aluminized screen, which provides violet fluorescence with extremely short persistence, making it ideal for rapid-decay display applications.
To ensure reliable operation, designers must adhere to the 12,000 V dc maximum anode rating, maintain accelerator voltage above 7,000 V dc to preserve brilliance and definition, and limit beam current density to prevent burning the sensitive P16 phosphor. Proper mechanical support, including a socket with a center opening to clear the tubulation, and adequate X-ray shielding at high operating voltages are required.
