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Specialized - Cathode Ray ·CathodeRay

7BMP1

Seven-inch rectangular single-gun CRT with electrostatic focusing and deflection and post acceleration. Its electron optics provide high brightness, small spot size, and reduced edge defocusing for instrument display.

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

Description

The ETC 7BMP1 is a seven-inch rectangular single-gun electrostatic-focus and deflection cathode-ray tube using post-acceleration for high brightness and small spot size while minimizing edge defocusing.

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 post-accelerator voltage

    16000 V

  • Maximum accelerator voltage

    8000 V

  • Maximum focusing voltage

    1750 V

  • Maximum accelerator-to-deflection-electrode voltage

    750 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 post-accelerator voltage

    10000 V

  • Typical accelerator voltage

    5000 V

  • Typical focusing voltage

    1000 to 1400 V

  • Typical grid-1 voltage

    -87 to -53 V

  • Post-accelerator to accelerator ratio maximum

    2

  • Modulation factor maximum

    45 V

Construction

  • Focusing method

    Electrostatic

  • Deflecting method

    Electrostatic

  • Electron gun / beam count

    1

Characteristic

  • Phosphor options

    P1,P2,P7,P11,P19

Capacitance

  • Cathode to all other electrodes

    5 pF

  • Grid 1 to all other electrodes

    6 pF

  • D1 to D2

    4 pF

  • D3 to D4

    1.6 pF