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Specialized - Cathode Ray ·CathodeRay

SC3875

Character-writing CRT using electrostatic focusing with combined magnetic and electrostatic character-writing deflection. Its P14 blue/yellow-orange screen supports electronically generated alphanumeric and vector information.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
DUODECAL6
Base pins
-
Nominal heater
6.3 V / 600 mA

Description

Sylvania SC3875 special-purpose CRT with electrostatic focus and magnetic + electrostatic character writing deflection; P14 blue/yellow-orange. Published high-voltage ratings, focus/deflection data, capacitances, circuit limits, and typical operating conditions were extracted from the supplied datasheet.

Socket description

Small-shell Duodecal 6-contact CRT base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
DUODECAL6
Base pins
-
Nominal heater voltage
6.3 V
Nominal heater current
600 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

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
18000 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

  • MinimumUsefulScreenDiameter

    17 in

Data set 02

1965 Sylvania Electronic Tubes Vol3

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristic

  • Heater Voltage

    6.3 V

  • Heater Current

    600 mA

  • FocusingMethod

    Electrostatic

  • DeflectionMethod

    Magnetic + electrostatic character writing

  • PhosphorOrScreen

    P14 blue/yellow-orange

  • UsefulScreenOrScan

    17 inch

  • SpotPositionMaximum

    Within 30 mm diameter

  • Grid1 To All Capacitance

    8 pF

  • Cathode To All Capacitance

    6 pF

Other

  • AnodeVoltageMaximum

    18000 V

  • Grid1NegativeBiasMagnitudeMaximum

    220 V

  • Grid1PositiveBiasMaximum

    0 V

  • Grid1PositivePeakVoltageMaximum

    2 V

  • Grid1CircuitResistanceMaximum

    1.5 Mohm

  • HeaterCathodeVoltageMaximum

    200 V

    AfterWarmup

  • Grid2VoltageTypical

    500 V

  • PeakVoltageAnodeToDeflectionPlate

    550 V

  • FocusElectrodeVoltageMinimum

    -500 V

  • FocusElectrodeVoltageMaximum

    1100 V

  • Grid2VoltageMaximum

    700 V

  • Anode Voltage

    15000 V

  • FocusElectrodeVoltage

    0 to +400 V

  • Grid1VoltageForCutoff

    -35 to -72 V

  • DeflectionFactorD1D2

    170 V/in

  • DeflectionFactorD3D4

    185 V/in

  • LineWidth

    0.025 in

    GridDriveService

  • DeflectionCircuitResistanceMaximum

    5 Mohm