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Specialized - Gauge Tube ·Gauge

8418

Hot-filament ionization gauge tube designed for measuring very low gas pressures below approximately 0.5 pascal.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
B9A
Base pins
9
Nominal heater
4.2 V / 4.2 A

Description

Ionization gauge tube for measuring very low gas pressures below about 0.5 pascal.

Socket description

Small-button Noval 9-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B9A
Base pins
9
Nominal heater voltage
4.2 V
Nominal heater current
4.2 A
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

Gauge

X-ray radiationInterelectrode capacitances
Max plate voltage
500 V
Max plate dissipation
5 W
Max grid dissipation
5 W

Ionisation-gauge collector/grid structure; promoted voltage/dissipation values are from measurement-mode absolute limits where semantically applicable.

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

1960 Mazda

Published operating points and test conditions from this source.

SECTION 1

Gauge

Other

  • Degassing filament voltage maximum

    6 V

  • Degassing grid-and-collector voltage maximum

    750 V

  • Degassing grid-and-collector dissipation maximum

    75 W

  • Degassing grid dissipation maximum

    7.5 W

  • Measurement filament voltage maximum

    4.5 V

  • Measurement grid current maximum

    25 mA

  • Measurement grid voltage maximum

    500 V

  • Measurement grid dissipation maximum

    5 W

  • Measurement filament voltage

    4.2 V

  • Measurement filament current

    4.2 A

  • Measurement grid voltage

    250 V

  • Measurement grid current

    10 mA

  • Measurement collector voltage

    -30 V

Characteristic

  • Argon sensitivity at stated conditions

    1370 uA/Pa

Data set 02

1968 Mazda Belvu

Published operating points and test conditions from this source.

SECTION 1

Gauge

Characteristics

  • Heater or filament voltage

    3.7 V

    Published nominal value

  • Heater or filament current

    4 A

    Published nominal value

  • Pressure measurement range

    0.0001 to 0.5 Pa

    Published useful calibration range

  • Ion gauge sensitivity

    1370 uA/Pa

    Argon; stated operating condition

Other

  • Maximum plate dissipation

    5 W

    Published limit