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Specialized - Cathode Ray ·CathodeRay

4NP1

Rectangular mono-accelerator instrument CRT designed for equipment exposed to extreme shock, severe vibration, and altitudes above 50,000 feet. Its ruggedized construction suits airborne or similarly demanding oscillographic installations.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
B12A
Base pins
-
Nominal heater
6.3 V / 600 mA

Description

The ETC 4NP1 is a 4 by 1.75 inch rectangular mono-accelerator cathode-ray tube designed for equipment subject to extreme shock, severe vibration, and altitudes above 50,000 feet.

Socket description

Duodecal 12-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B12A
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.

Cathode-ray electron-gun section; CRT-specific ratings are retained in TUBE_SECTION_PARAMETER because fixed plate/screen fields are not semantically equivalent.

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

1961 Electronic Tube Corp

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Other

  • Heater voltage

    6.3 V

  • Heater current nominal

    600 mA

  • Maximum accelerator voltage

    3000 V

  • Maximum focusing voltage

    1500 V

  • Maximum accelerator-to-deflection-electrode voltage

    550 V

  • Maximum negative grid-1 bias magnitude

    200 V

  • Maximum positive grid-1 bias

    0 V

  • Maximum heater-to-cathode voltage magnitude

    180 V

  • Typical accelerator voltage

    2500 V

  • Typical focusing voltage

    610 to 710 V

  • Typical grid-1 voltage

    -100 to -60 V

  • Maximum operating altitude

    70000 ft

  • Useful scan D1-D2

    3.5 in

  • Useful scan D3-D4

    1.25 in

Construction

  • Focusing method

    Electrostatic

  • Deflecting method

    Electrostatic

  • Electron gun / beam count

    1

Characteristic

  • Phosphor options

    P1,P2,P7,P11

Capacitance

  • Cathode to all other electrodes

    4.5 to 5.5 pF

  • Grid 1 to all other electrodes

    4 to 5 pF