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Specialized - Cathode Ray ·CathodeRay

SC3895

Nineteen-inch character-writing CRT for large-screen alphanumeric and vector display, using electrostatic focusing and deflection with post-deflection acceleration for a bright, precisely written image.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
B12-37
Socket code
B14
Base pins
14
Nominal heater
6.3 V / 600 mA

Description

Nineteen-inch character-writing CRT for large-screen alphanumeric and vector display, with electrostatic focus/deflection and post-deflection acceleration.

Socket description

Small-shell Diheptal 14-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
B12-37
Socket code
B14
Base pins
14
Nominal heater voltage
6.3 V
Nominal heater current
600 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

B12-37 - Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

1 physical section, each with unique specifications.

Section 1

Cathode Ray

X-ray radiationInterelectrode capacitances
Max plate voltage
19800 V

Ratings and characteristics promoted from the supplied Sylvania source where explicitly published.

Source-dependent data

Operating conditions by source

Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.

Data set 01

1950 Sylvania

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristic

  • HeaterOrFilamentVoltage

    6.3 V

  • HeaterOrFilamentCurrent

    600 mA

Other

  • PostAcceleratorVoltage

    19800 V

Data set 02

1965 Sylvania Electronic Tubes Vol3

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Other

  • Heater voltage

    6.3 V

  • Heater current

    540 mA to 660 mA

  • Anode input maximum

    6 W

  • Anode No. 3 post-accelerator voltage maximum

    19800 V

  • Anode No. 2 voltage maximum

    11000 V

  • Anode No. 1 focus-electrode voltage maximum

    8000 V

  • Grid No. 1 negative bias maximum

    -200 V

  • Grid No. 1 positive bias maximum

    0 V

  • Grid No. 1 positive peak maximum

    0 V

  • Grid No. 2 voltage maximum

    800 V

  • Peak heater-cathode voltage maximum

    180 V

  • Peak Anode No. 2 to deflecting-plate voltage maximum

    1500 V

  • Anode No. 3 post-accelerator voltage

    18000 V

  • Anode No. 2 voltage

    10000 V

  • Grid No. 2 voltage

    500 V

  • Anode No. 1 focus voltage

    4800 to 5200 V

  • Grid No. 1 cutoff voltage

    -150 to -50 V

  • Focus correction maximum

    1000 V

  • Astigmatism correction maximum

    350 V

Capacitance

  • Cathode to all other electrodes capacitance

    7.5 pF

  • Grid No. 1 to all other electrodes capacitance

    14 pF

  • Between deflecting plates 1-2 capacitance

    6.4 pF

  • Between deflecting plates 3-4 capacitance

    2.5 pF

  • Deflecting plate 1 to all other electrodes capacitance

    13.7 pF

  • Deflecting plate 2 to all other electrodes capacitance

    13.7 pF

  • Deflecting plate 3 to all other electrodes capacitance

    5.7 pF

  • Deflecting plate 4 to all other electrodes capacitance

    5.7 pF

  • Grid No. 2 to all other electrodes capacitance

    13.5 pF

Characteristic

  • Deflection factor plates 1-2

    90 to 140 V/in

  • Deflection factor plates 3-4

    90 to 140 V/in

  • Center line width

    0.025 in

  • Corner line width

    0.04 in

CircuitValue

  • Grid No. 1 circuit resistance maximum

    1.5 Mohm

  • Deflection-plate circuit resistance maximum

    1 Mohm