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Specialized - Cathode Ray ·CathodeRay

SC3850

High-resolution special-purpose CRT with magnetic focusing and deflection and a fine-grain P11 fiber-optic screen, optimized for detailed fast optical image coupling.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
DUODECAL5
Base pins
-
Nominal heater
6.3 V / 600 mA

Description

Sylvania SC3850 special-purpose CRT with magnetic focus and magnetic deflection; fine-grain P11 fiber-optic. 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 5-contact CRT base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
DUODECAL5
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
15000 V

Special-purpose cathode-ray tube; published ratings and construction data captured.

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

Characteristics

  • Focusing method

    Electrostatic

  • Deflection method

    Magnetic

Application

  • Application

    Electrostatic charge printing

Construction

  • Fiber optics faceplate

    Yes

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

    Magnetic

  • DeflectionMethod

    Magnetic

  • PhosphorOrScreen

    fine-grain P11 fiber-optic

  • UsefulScreenOrScan

    4 x 0.5 inch fiber-optic

  • ExternalCoatingToAnodeCapacitanceMinimum

    100 pF

  • ExternalCoatingToAnodeCapacitanceMaximum

    500 pF

  • FiberSize

    5 um

  • NumericalAperture

    0.84

  • Grid1 To All Capacitance

    7.5 pF

  • Cathode To All Capacitance

    5 pF

Other

  • AnodeVoltageMaximum

    15000 V

  • Grid1NegativeBiasMagnitudeMaximum

    220 V

  • Grid1PositiveBiasMaximum

    0 V

  • Grid1PositivePeakVoltageMaximum

    2 V

  • Grid1CircuitResistanceMaximum

    1.5 Mohm

  • HeaterCathodeVoltageMaximum

    200 V

    AfterWarmup

  • Grid2VoltageTypical

    2000 V

  • AnodeCurrentMaximum

    3 uA

  • Grid2VoltageMaximum

    2500 V

  • Grid2CurrentMaximum

    2000 uA

  • Anode Voltage

    10000 V

  • FocusElectrodeVoltage

    magnetic V

  • Grid1VoltageForCutoff

    -33 to -77 V

  • LineWidth

    0.0008 in