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Specialized - Cathode Ray ·CathodeRay

SC2809

Five-inch high-resolution photographic-recording CRT with magnetic focusing and deflection and an extremely fine-grain P11 screen, designed by Sylvania for precision trace photography.

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

Description

The Sylvania SC2809 is a 5-inch high-resolution photographic-recording CRT with magnetic focus and deflection and an extremely fine-grain P11 screen.

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

No fixed ratings are recorded for this section.

High-resolution photographic CRT electron-gun/display section.

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

1965 Sylvania Electronic Tubes Vol3

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristics

  • Heater Voltage

    6.3 V

  • Heater Current

    600 mA

  • Focusing Method

    Magnetic text

  • Deflection Method

    Magnetic text

  • Deflection Angle

    50 deg

    Approximate

  • Phosphor

    Fine Grain Aluminized P11 text

  • Fluorescence

    Blue text

  • Persistence

    Short text

  • Line Width

    0.0008 in

    HighResolution

Other

  • Maximum Anode Voltage

    25000 V

  • Maximum Grid2 Voltage

    2500 V

  • Maximum Grid1 Negative Bias

    150 V

  • Maximum Heater-Cathode Voltage During Warmup

    450 V

  • Maximum Heater-Cathode Voltage After Warmup

    165 V

  • Anode Voltage

    20000 V

    PhotographicRecording

  • Grid2 Voltage

    2000 V

    PhotographicRecording

  • Grid1 Cutoff Voltage Minimum

    -77 V

  • Grid1 Cutoff Voltage Maximum

    -33 V

  • Focusing Coil Current

    100 mA

    Approximate

  • Maximum Grid1 Circuit Resistance

    1.5 Mohm