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Voltage Pentode or Tetrode (under 100V) ·Pentode

CK5889

Subminiature directly heated electrometer pentode designed for measurement of extremely small currents, with exceptionally low control-grid current.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
4G
Socket code
-
Base pins
4
Nominal heater
1.25 V / 7.5 mA

Description

Subminiature directly heated electrometer pentode with extremely high plate resistance and ultra-low grid current.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
4G
Socket code
-
Base pins
4
Nominal heater voltage
1.25 V
Nominal heater current
7.5 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

4G - 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

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
18000000 Ω
Transconductance
0.000014 S
Max plate voltage
12 V
Max screen voltage
4.5 V

Promoted only from clearly identified printed electrical values; additional values retained in TUBE_SECTION_PARAMETER.

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

195X Raytheon Special Purpose Tubes

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate voltage

    12 V

    Electrometer

  • Control-grid voltage

    -2 V

    Electrometer

  • Screen voltage

    4.5 V

    Electrometer

  • Plate current

    0.005 mA

    Electrometer

  • Screen current

    0.005 mA

    Electrometer

  • Maximum control-grid current

    0.000000000003 mA

    Electrometer

Characteristic

  • Plate resistance

    18 MΩ

    Electrometer

  • Transconductance

    14 µS

    Electrometer