Specialized - Cathode Ray ·CathodeRay
Twelve-inch P7 long-persistence radar-indicator cathode-ray tube with magnetic focusing and deflection. Its aluminized gray-filter screen gives blue-white fluorescence with yellow afterglow, and the anode is rated to about 15 kV.
The Sylvania 12SP7D is a 12-inch P7 long-persistence radar-indicator cathode-ray tube with magnetic focus and deflection.
Duodecal 12-contact
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
Published maximum ratings and characteristics promoted semantically from the approved source.
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 Plate Voltage
15000 V
Typical Anode Voltage
9000 V
Phosphor
P7
Focusing Method
Magnetic
Deflecting Method
Magnetic
Data set 02
Published operating points and test conditions from this source.
Heater Voltage
6.3 V
Heater Current
600 mA
Focusing Method
Magnetic text
Deflection Method
Magnetic text
Fluorescence
Blue-White text
Persistence
Long text
Phosphorescence
Yellow text
Deflection Angle
54 deg
Approximate
Screen Aluminized
Yes text
Faceplate
Gray Filter Glass text
Maximum Undeflected Spot Radius
20 mm
Light Transmittance
74 percent
Approximate
Maximum Anode Voltage
15000 V
Maximum Grid2 Voltage
770 V
Maximum Grid1 Negative Bias
200 V
Maximum Grid1 Positive Peak
2 V
Maximum Heater-Cathode Voltage
200 V
EitherPolarity
Anode Voltage
9000 V
Grid2 Voltage
250 V
Grid1 Cutoff Voltage Minimum
-63 V
Grid1 Cutoff Voltage Maximum
-27 V
Focusing Coil Current
110 mA
Approximate
Maximum Grid1 Circuit Resistance
1.5 Mohm