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Specialized - Cathode Ray ·CathodeRay

SC2558

Twelve-inch long-persistence P7 oscilloscope CRT with electrostatic focusing and deflection plus post-deflection acceleration. Sylvania specifies high-voltage operation to approximately 12 kV for persistent waveform display.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
DIHEPTAL12
Base pins
-
Nominal heater
6.3 V / 600 mA

Description

The Sylvania SC2558 is a 12-inch long-persistence P7 oscilloscope CRT with electrostatic focus and deflection and post-deflection acceleration.

Socket description

Medium-shell Diheptal 12-contact CRT base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
DIHEPTAL12
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
12000 V

Published ratings and characteristics promoted semantically from the approved source.

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

Other

  • Maximum Plate Voltage

    12000 V

  • Typical Anode Voltage

    10000 V

Characteristic

  • Phosphor

    P7

  • Focusing Method

    Electrostatic

  • Deflecting Method

    Electrostatic

Data set 02

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

    Electrostatic text

  • Deflection Method

    Electrostatic text

  • Phosphor

    P7 text

  • Fluorescence

    Blue-White text

  • Phosphorescence

    Yellow text

  • Persistence

    Long text

  • Cathode-to-All Capacitance

    10 pF

  • Grid1-to-All Capacitance

    8 pF

  • Deflection Plates 1-2 Capacitance

    4 pF

  • Deflection Plates 3-4 Capacitance

    2 pF

Other

  • Maximum Post-Accelerator Voltage

    20000 V

    Representative

  • Maximum Grid1 Circuit Resistance

    1.5 Mohm