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Tube Tinker — Electron Tube Database
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Specialized - Ballast ·Ballast

40A1

Gas-filled ballast tube designed for nearly constant-current operation, specifically used as a television horizontal-output cathode stabilizer.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
OCTAL5
Base pins
-
Nominal heater
-

Description

Gas-filled ballast tube that maintains nearly constant current and is used as a horizontal-output cathode stabilizer in television receivers.

Socket description

Small-wafer octal 5-contact base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
OCTAL5
Base pins
-
Nominal heater voltage
-
Nominal heater current
-
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

Ballast

X-ray radiationInterelectrode capacitances

No fixed ratings are recorded for this section.

Published ratings and characteristics promoted semantically from the approved source.

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

Ballast

Other

  • Maximum Cathode Current

    9 mA

  • Minimum Operating Voltage

    20 V

  • Maximum Operating Voltage

    60 V

Characteristic

  • Average Operating Current

    7.4 mA

    20 V

  • Average Operating Current

    8.4 mA

    40 V

  • Average Operating Current

    9 mA

    60 V