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Specialized - Cathode Ray ·CathodeRay

2104HB

Twenty-one-inch radar display CRT with magnetic focusing and magnetic deflection through approximately 90 degrees. Its orange H-type phosphor has very long persistence, retaining radar traces and echoes for extended viewing.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
6.3 V / 300 mA

Description

21-inch radar CRT with magnetic focus/deflection, 90-degree deflection, and very-long-persistence orange screen.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
-
Nominal heater voltage
6.3 V
Nominal heater current
300 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

Published Ferranti ratings, capacitances, and typical operating data promoted where applicable; additional electrical values 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

1963 Ferranti

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristics

  • Focusing method

    Magnetic

  • Deflection method

    Magnetic

  • Deflection angle

    90 deg

  • Fluorescence

    Orange

  • Persistence

    Very long

Construction

  • Phosphor type

    H

Application

  • Application

    Radar / monitor / display CRT

Other

  • First-anode voltage maximum

    500 V

  • First-anode voltage minimum

    200 V

  • Second-anode operating voltage

    16000 V

  • Heater-cathode voltage maximum

    200 V

  • First-anode operating voltage

    300 V

  • Grid visual-cutoff voltage range

    -40 to -80 V

Capacitance

  • Cathode-to-all capacitance maximum

    8 pF

  • Grid-to-all capacitance maximum

    8 pF

  • External-coating capacitance approximate

    1500 pF