Data set 01
1961 Tung Sol
Published operating points and test conditions from this source.
Cathode Ray
Other
HighVoltageAnodeMaximum
20000 V
CRT
Capacitance
CathodeToOtherElectrodesCapacitance
5 pF
Approximate
Specialized - Cathode Ray ·CathodeRay
Twenty-one-inch rectangular direct-view television picture tube with electrostatic focus, magnetic deflection, gray-filter faceplate, external single-field ion trap, and white P4 medium-persistence screen for monochrome receiver service.
A-version of the 21KP4 electrostatically focused, magnetically deflected television picture tube.
Duodecar 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 promoted fields populated by printed ratings/characteristics headings.
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.
HighVoltageAnodeMaximum
20000 V
CRT
CathodeToOtherElectrodesCapacitance
5 pF
Approximate
Data set 02
Published operating points and test conditions from this source.
Focusing method
Electrostatic
Deflecting method
Magnetic
Phosphor
P4
White;MediumPersistence
Deflection angle
70 deg
Approximate
Faceplate light transmission at center
66 %
Approximate
Heater voltage
6.3 V
Heater current
600 mA
Maximum DC anode voltage
15000 V
Maximum DC grid #2 voltage
410 V
Maximum grid #1 negative-bias magnitude
125 V
Maximum grid #1 positive DC voltage
0 V
Maximum grid #1 positive peak voltage
2 V
Typical DC anode voltage
12000 V
TelevisionPictureTube
Typical DC grid #2 voltage
300 V
TelevisionPictureTube
Typical grid #1 voltage minimum
-77 V
VisualExtinctionRange
Typical grid #1 voltage maximum
-33 V
VisualExtinctionRange
Maximum grid #1 circuit resistance
1.5 megohm
Ion trap magnet rated strength
50 gauss
Approximate
Focusing electrode voltage minimum
-500 V
ElectrostaticFocus
Focusing electrode voltage maximum
1000 V
ElectrostaticFocus
Centering magnet field strength maximum
8 gauss
Approximate
Cathode-to-all-other-electrodes capacitance
6 pF
Approximate
Grid #1-to-all-other-electrodes capacitance
6.5 pF
Approximate
Application
Direct-view television picture tube