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Specialized - Cathode Ray ·CathodeRay

2F21

Five-inch monoscope with electrostatic focusing, magnetic deflection, and an internal pattern electrode. RCA designed it to generate fixed television and test patterns electronically rather than display an externally supplied image.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
OCTALCRT8
Base pins
-
Nominal heater
6.3 V / 600 mA

Description

Five-inch monoscope with electrostatic focus, magnetic deflection, and internal pattern electrode for television/test-pattern generation.

Socket description

Octal 8-contact CRT base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
OCTALCRT8
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
1500 V
Max screen voltage
600 V

Monoscope; pattern electrode and collector ratings retained as parameters.

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

1971 RCA HB3 Binder 1 of 7

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Other

  • Heater voltage

    6.3 V

  • Heater current

    600 mA

  • Pattern electrode voltage maximum

    1500 V

  • Grid #4 collector voltage maximum

    1500 V

  • Grid #3 focusing voltage maximum

    600 V

  • Peak heater-cathode voltage

    125 V

Construction

  • Focusing method

    Electrostatic

  • Deflection method

    Magnetic

Characteristic

  • Maximum solid deflection angle

    40 deg

  • Pattern calibration

    Up to 500 lines