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Tube Tinker — Electron Tube Database
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Specialized - Cathode Ray ·CathodeRay

3WP2

Three-inch high-deflection-sensitivity oscilloscope CRT with a flat clear faceplate, electrostatic focusing, and electrostatic deflection. Its construction is optimized for precise direct viewing of instrument waveforms.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
OCTALCRT8
Base pins
-
Nominal heater
6.3 V / 600 mA

Description

Three-inch high-deflection-sensitivity direct-view oscilloscope CRT with flat clear faceplate, electrostatic focus, and electrostatic deflection.

Socket description

Octal 8-contact CRT base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
OCTALCRT8
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-specific electrode voltages, deflection factors, capacitances, focus/cutoff data, and other published electrical values are stored as section parameters because the promoted section columns are primarily conventional valve fields.

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

1950 Sylvania

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristic

  • Phosphor

    P2

  • Focusing Method

    Electrostatic

  • Deflecting Method

    Electrostatic

Other

  • Typical Anode No. 2 Voltage

    2000 V

Data set 02

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

    62 V/in

  • Deflection factor D1-D2 maximum

    76 V/in

  • Deflection factor D3-D4 minimum

    43 V/in

  • Deflection factor D3-D4 maximum

    52 V/in

  • Useful screen / scan

    1 code

    2.75-inch minimum useful screen diameter

  • Phosphor designation

    1 code

    P2

  • Deflection factor uniformity maximum

    2 %

  • Pattern distortion maximum

    2.5 %

    At75PercentUsefulScan

  • Useful scan D1-D2

    2.5 in

    MinimumTotal

  • Useful scan D3-D4

    2.25 in

    MinimumTotal

Other

  • Anode No. 2 / accelerator voltage

    1500 V

  • Focusing electrode voltage minimum

    247 V

  • Focusing electrode voltage maximum

    465 V

  • Grid No. 1 cutoff voltage minimum

    -75 V

  • Grid No. 1 cutoff voltage maximum

    -45 V

  • Grid No. 1 negative bias maximum

    200 V

Capacitance

  • Cathode to all other electrodes minimum

    3 pF

    Approximate or published bound

  • Cathode to all other electrodes maximum

    5.7 pF

    Approximate or published bound

  • Grid No. 1 to all other electrodes minimum

    4.6 pF

    Approximate or published bound

  • Grid No. 1 to all other electrodes maximum

    8.7 pF

    Approximate or published bound

  • Deflection plates 1-2 capacitance minimum

    1.7 pF

    Approximate or published bound

  • Deflection plates 1-2 capacitance maximum

    3.3 pF

    Approximate or published bound

  • Deflection plates 3-4 capacitance minimum

    1 pF

    Approximate or published bound

  • Deflection plates 3-4 capacitance maximum

    2 pF

    Approximate or published bound