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Tube Tinker — Electron Tube Database
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Specialized - Ballast ·Ballast

40B2

Gas-filled ballast tube designed to maintain relatively constant current throughout its specified operating-voltage range.

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

Description

Gas-filled ballast tube designed to maintain relatively constant current over a specified operating-voltage range.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
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

    160 mA

  • Minimum Operating Voltage

    20 V

  • Maximum Operating Voltage

    80 V

  • Minimum Current

    135 mA

  • Maximum Current

    160 mA

Characteristic

  • Average Operating Current

    140 mA

    20 V

  • Average Operating Current

    150 mA

    40 V

  • Average Operating Current

    155 mA

    80 V