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Specialized - Cathode Ray ·CathodeRay

3ASP11

Three-inch oscilloscope and instrument cathode-ray tube with electrostatic focusing and electrostatic deflection and a P11 screen. Manufacturer documentation supports compact waveform, measurement, and indicator-display service.

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

Description

Electrostatically focused and deflected oscilloscope/instrument CRT with P11 phosphor.

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
Max plate voltage
3000 V

Published electrostatic CRT ratings, focus/deflection conditions, capacitances, and post-deflection-acceleration data retained where legible.

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

    Electrostatic

  • Deflection method

    Electrostatic

  • Heater voltage

    6.3 V

  • Heater current

    600 mA

  • Fluorescence

    Blue

  • P1 light output minimum

    20 foot-lambert

  • Modulation maximum

    38 V

  • Line width maximum

    0.65 mm

Application

  • Application

    Oscilloscope / precision instrument display

Other

  • Typical anode-2 voltage

    2000 V

  • Focus voltage range

    400 to 700 V

  • Grid cutoff voltage range

    -40 to -70 V

  • Grid1 circuit resistance maximum

    1.5 Mohm

  • Deflection-circuit resistance maximum

    1 Mohm