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Specialized - Cathode Ray ·CathodeRay

5BPA

Five-inch electrostatic oscilloscope and instrument cathode-ray tube designed for direct waveform display. Manufacturer documentation specifies the electron-optical system, screen characteristics, ratings, capacitances, and representative operating conditions.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
11N
Socket code
MAGNAL11
Base pins
11
Nominal heater
6.3 V / 600 mA

Description

The 5BPA is a 5-inch cathode-ray tube described by Sylvania as a electrostatic oscilloscope CRT. Its supplied sheet specifies a 6.3 V heater, electrode/anode ratings, focus and deflection conditions, interelectrode capacitances, and a P1 green fluorescence, medium persistence screen.

Socket description

Magnal 11-contact base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
11N
Socket code
MAGNAL11
Base pins
11
Nominal heater voltage
6.3 V
Nominal heater current
600 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

11N - 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
2200 V

CRT highest published anode/accelerating voltage is promoted to MaxPlateVoltage; additional electrode, deflection, optical, and capacitance data are retained as parameters.

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

Capacitance

  • Grid No. 1 to all other electrodes capacitance

    8 pF

  • Deflection plates 1-2 capacitance

    1.3 pF

  • Deflection plates 3-4 capacitance

    1.2 pF

  • Deflection plate 1 to all other electrodes capacitance

    9.5 pF

  • Deflection plate 3 to all other electrodes capacitance

    12 pF

  • Deflection plate 1 to all other electrodes except D2 capacitance

    8 pF

  • Deflection plate 2 to all other electrodes except D1 capacitance

    7.5 pF

  • Deflection plate 3 to all other electrodes except D4 capacitance

    10 pF

  • Deflection plate 4 to all other electrodes except D3 capacitance

    7.5 pF

Other

  • Maximum anode No. 2 voltage

    2200 V

  • Maximum anode No. 1 voltage

    1100 V

  • Maximum negative grid bias magnitude

    125 V

  • Peak voltage between anode No. 2 and any deflection plate

    550 V

  • Typical anode No. 2 voltage

    2000 V

  • Focus voltage range

    315 to 562 V

  • Grid cutoff voltage range

    -60 to -20 V

  • Deflection factor plates 1-2

    70 to 98 V/in

  • Deflection factor plates 3-4

    63 to 89 V/in

CircuitValue

  • Grid No. 1 circuit resistance maximum

    1.5 MOhm

  • Deflection circuit resistance maximum

    5 MOhm