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Specialized - Cathode Ray ·CathodeRay

7BPA

Seven-inch direct-view cathode-ray display tube with electrostatic focusing and magnetic deflection. Sylvania publishes heater, capacitance, electrode-rating, operating-condition, and mechanical data for general indicator and display service.

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

Description

7BPA is a direct-view cathode-ray display tube intended for television, radar, or indicator service. Its Sylvania datasheet provides heater data, interelectrode capacitances, electrode ratings, operating conditions, and mechanical information; focusing is electrostatic and deflection is magnetic.

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
6.5 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.

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

Characteristic

  • Heater current

    600 mA

    Published heater current

  • Heater voltage

    6.5 V

    Published heater voltage

Other

  • Anodevoltage . . •

    8800 V

    Anodevoltage . . • 8,800 Volts dc

  • GridNo.2Voltage

    770 V

    GridNo.2Voltage . 770 Volts dc

  • Heater Negative with Respect to Cathode

    140 V

    Heater Negative with Respect to Cathode 140 Volts

  • Heater Positive with Respect to Cathode

    140 V

    Heater Positive with Respect to Cathode . 140 Volts

  • Grid No. 1 Circuit Resistance

    1.5 Mohm

    Grid No. 1 Circuit Resistance . 1.5 Megohms Max. TECHPN'];8#LdpaundBLiR=L%f%£ysTfecTioN