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Specialized - Cathode Ray ·CathodeRay

DG251

Philips/Mullard DG-series cathode-ray instrument tube intended for oscillographic and measurement display, with manufacturer-defined electrostatic focusing, deflection, screen, and accelerating characteristics for type DG251.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
4 V / 1.2 A

Description

DG251 is a CathodeRay device in the supplied Philips literature. Philips high-vacuum cathode-ray tube for television receiver service with green fluorescent screen and double electrostatic deflection.

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
4 V
Nominal heater current
1.2 A
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.

Philips high-vacuum cathode-ray tube for television receiver service with green fluorescent screen and double electrostatic deflection.

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

1938 Philips Miniwatt Vacuum Tube Catalog

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Other

  • Screen diameter

    257 mm

  • Greatest overall length

    580 mm

  • Greatest length without pins

    550 mm

  • Maximum third-anode voltage

    5000 V

  • Maximum second-anode voltage

    1700 V

  • Maximum first-anode voltage

    250 V

  • Maximum grid bias for ray suppression

    -60 V

  • Third-anode voltage

    5000 V

  • Second-anode voltage

    1400 V

  • First-anode voltage

    250 V

Characteristic

  • Deflection sensitivity N1

    0.13 mm/V

  • Deflection sensitivity N2

    0.11 mm/V

Capacitance

  • Grid capacitance

    15 pF

  • Deflection-plate capacitance D1-D1'

    5.5 pF

  • Deflection-plate capacitance D2-D2'

    6.5 pF

Data set 02

1999 Philips 0-D

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristics

  • Screen diameter

    25 cm

    Published datasheet value

  • Screen fluorescence

    Green for DG25-1; blue for DB25-1

    Published datasheet value

  • Focusing

    Electrostatic

    Published datasheet value

  • Deflection

    Electrostatic

    Published datasheet value

Other

  • Filament voltage

    4 V

    Published datasheet value

  • Filament current

    approx. 2.3 A

    Published datasheet value