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Specialized - Cathode Ray ·CathodeRay

4MP11

Three-and-one-half-inch square direct-view oscilloscope CRT with electrostatic focusing and deflection plus post-deflection acceleration. Its P11 screen provides a blue short-persistence trace for rapidly changing waveforms.

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

Description

Three-and-one-half-inch square direct-view oscilloscope CRT with electrostatic focus, electrostatic deflection, and post-deflection acceleration.

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.

CRT electron-gun/display section; CRT-specific electrical ratings, capacitances, focus and deflection data are stored in TUBE_SECTION_PARAMETER.

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

1965 Sylvania Electronic Tubes Vol3

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristics

  • Focusing method

    1 code

    Electrostatic

  • Deflection method

    1 code

    Electrostatic

  • Deflection factor D1-D2 minimum

    68 V/in

  • Deflection factor D1-D2 maximum

    82 V/in

  • Deflection factor D3-D4 minimum

    42 V/in

  • Deflection factor D3-D4 maximum

    52 V/in

  • Useful screen / scan

    1 code

    2.875 x 2.875-inch minimum useful square scan

  • Phosphor designation

    1 code

    P11

  • Deflection factor uniformity maximum

    2 %

  • Pattern distortion maximum

    2 %

  • Useful scan

    2.875 in

    MinimumSquareDimension

Other

  • Anode No. 2 / accelerator voltage maximum

    3300 V

  • Post-accelerator / Anode No. 3 voltage maximum

    6600 V

  • Anode No. 2 / accelerator voltage

    2000 V

  • Post-accelerator / Anode No. 3 voltage

    4000 V

  • Focusing electrode voltage maximum

    1100 V

  • Focusing electrode voltage minimum

    340 V

  • Focusing electrode voltage maximum

    510 V

  • Grid No. 1 cutoff voltage minimum

    -87 V

  • Grid No. 1 cutoff voltage maximum

    -52 V

  • Peak heater-to-cathode voltage

    200 V

  • Peak voltage between accelerator and any deflection plate

    600 V

  • Grid No. 1 negative bias maximum

    200 V