Specialized - Cathode Ray ·CathodeRay
Seventeen-inch direct-view monochrome television picture tube with electrostatic focus, magnetic deflection, gray/filter faceplate, and aluminized P4 white screen. Its high-voltage design includes an X-ray warning and conventional receiver-display operating characteristics.
The 17DWP4 is a 17-inch, rectangular glass picture and television monitor tube designed for high-resolution display applications. It features a spherical faceplate, an aluminized screen, low-voltage electrostatic focusing, and magnetic deflection. The design does not require an ion-trap magnet, simplifying the deflection yoke and neck components.
The 17DWP4 is constructed with a rectangular glass bulb (J133B or J133D) and a gray filterglass faceplate. The faceplate provides approximately 74% light transmission, which improves contrast under ambient light conditions.
The screen utilizes an aluminized P4-Sulfide Type phosphor that exhibits white fluorescence with short-to-medium persistence. To prevent electrostatic charge buildup and assist in high-voltage filtering, the tube is equipped with a Regular-Band type external conductive coating. This coating must be grounded during operation, with the grounding contact area located near the reference line.
| Parameter | Value |
|---|---|
| Overall Length | 19-3/16" ± 3/8" |
| Neck Length | 7-1/2" ± 3/16" |
| Maximum Useful Screen Diagonal | 17" (approximate) |
| Maximum Useful Screen Width | 14-5/16 inches |
| Maximum Useful Screen Height | 11-1/8 inches |
| Minimum Projected Screen Area | 149 sq. inches |
| Approximate Weight | 18 lbs |
| Operating Position | Any |
The 17DWP4 uses a Small-Shell Duodecal 6-Pin base (JEDEC Group 4, No. B6-63) with a 12L basing designation (viewed from the bottom). High voltage is applied via a recessed small cavity cap (JEDEC No. J1-21) located on the bulb side.
The focusing electrode (Grid No. 4) pin connection (Pin 6) is aligned within 30 degrees of the horizontal centerline on the same side as the anode contact.
The heater is designed for AC or DC operation. The direct interelectrode capacitances are relatively low, minimizing loading on the driving circuitry.
The nominal heater power is calculated as 6.3 V × 0.6 A = 3.78 W, using the nominal heater voltage and current values.
The tube's ratings are specified under both Design-Maximum and Absolute Maximum rating systems. These limits must not be exceeded under any operating conditions.
| Parameter | Design-Maximum | Absolute Maximum |
|---|---|---|
| Ultor (Anode) Voltage | 22,000 V | 22,000 V dc |
| Grid No. 4 (Focusing) Voltage | 800 V (Positive) | -550 to +1100 V dc |
| Grid No. 2 Voltage | 700 V | 700 V dc |
| Grid No. 1 Negative Bias Value | 180 V | 180 V dc |
| Grid No. 1 Negative Peak Value | — | 220 V dc |
| Grid No. 1 Positive Bias Value | 0 V | 0 V dc |
| Grid No. 1 Positive Peak Value | 2 V | 2 V |
| Grid No. 1 Circuit Resistance | — | 1.5 Megohms max. |
Under typical operating conditions, the 17DWP4 is operated with an ultor voltage of 18,000 V dc. The focusing voltage is adjusted to achieve the sharpest spot or raster.
The 17DWP4 utilizes magnetic deflection with approximate deflection angles of:
Focusing is achieved via a low-voltage electrostatic lens (Grid No. 4). Because the focusing voltage range spans from 0 to 400 V dc, the focusing electrode can often be connected to a low-voltage supply or potentiometer in the receiver or monitor, eliminating the need for high-voltage focusing controls.
When operated at anode voltages above 16,000 V, the 17DWP4 can produce X-rays. Although the glass envelope provides some shielding, additional external shielding may be necessary if the tube is operated near or at its maximum rated anode voltage of 22,000 V. This is particularly important to prevent prolonged close-range exposure to operators or service technicians.
The external conductive coating must be reliably connected to the chassis ground. Failure to ground this coating can result in high-voltage shocks, erratic operation, or damage to associated electronic components due to electrostatic discharge.
Small-shell Duodecal 6-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 ratings, operating conditions, capacitances, focus/deflection, cutoff, optical, and screen data are retained in section 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.
Heater Voltage
6.3 V
Heater Current
600 mA
Cathode To All Other Electrodes Capacitance
5 pF
Approximate
Maximum Anode Voltage
22000 V
Maximum Grid2 Voltage
700 V
Typical Anode Voltage
18000 V
Data set 02
Published operating points and test conditions from this source.
Focusing method
Electrostatic
Deflection method
Magnetic
Horizontal deflection angle
65 deg
Diagonal deflection angle
70 deg
Vertical deflection angle
50 deg
Fluorescence
White
Persistence
Short to medium
Heater voltage
6.3 V
Heater current
600 mA
Phosphor
Aluminized P4
Maximum anode voltage
22000 V
Typical anode voltage
16000 V
Typical focus-electrode voltage maximum
400 V
Typical grid2 voltage
500 V
Cutoff voltage range
-35 to -72 V
Grid1 circuit resistance maximum
1.5 Mohm
Grid1-to-all capacitance
6 pF
External conductive coating to anode capacitance maximum
1500 pF
Application
Monochrome television picture display
Data set 03
Published operating points and test conditions from this source.
LOW-VOLTAGE ELECTROSTATIC FOCUS
70 V
Published CRT datasheet value; multiple numbers on one source row represent its separate limits or operating conditions.
Heater Current at 6.3 volts — published value 1
6.3 V
Published CRT datasheet value; multiple numbers on one source row represent its separate limits or operating conditions.
Heater Current at 6.3 volts — published value 2
600 V
Published CRT datasheet value; multiple numbers on one source row represent its separate limits or operating conditions.
Heater Current at 6.3 volts — published value 3
10 V
Published CRT datasheet value; multiple numbers on one source row represent its separate limits or operating conditions.
Grid No.l to all other electrodes
65
Published CRT datasheet value; multiple numbers on one source row represent its separate limits or operating conditions.
Light transmission (Approx )
74
Published CRT datasheet value; multiple numbers on one source row represent its separate limits or operating conditions.
Projected Area of Screen
149
Published CRT datasheet value; multiple numbers on one source row represent its separate limits or operating conditions.
Grid-No.4 Voltage for focus — published value 1
0 V
Published CRT datasheet value; multiple numbers on one source row represent its separate limits or operating conditions.
Grid-No.4 Voltage for focus — published value 2
400 V
Published CRT datasheet value; multiple numbers on one source row represent its separate limits or operating conditions.
extinction of focused raster — published value 1
-28 V
Published CRT datasheet value; multiple numbers on one source row represent its separate limits or operating conditions.
extinction of focused raster — published value 2
-72 V
Published CRT datasheet value; multiple numbers on one source row represent its separate limits or operating conditions.
ULTOR VOLTAGE
22000 V
Published CRT datasheet value; multiple numbers on one source row represent its separate limits or operating conditions.
GRID-No.2 VOLTAGE
700 V
Published CRT datasheet value; multiple numbers on one source row represent its separate limits or operating conditions.