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Voltage Tetrode ·Tetrode

259A

Western Electric screen-grid tetrode for high-frequency or audio-frequency voltage amplification and detector service, providing high voltage gain per stage.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
MEDIUM5
Base pins
5
Nominal heater
2 V / 1.6 A

Description

Western Electric 259A is a screen-grid tetrode for high-frequency or audio-frequency voltage amplification and detector service, with high gain per stage.

Socket description

Medium 5-contact transmitting-tube base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
MEDIUM5
Base pins
5
Nominal heater voltage
2 V
Nominal heater current
1.6 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

Tetrode

X-ray radiationInterelectrode capacitances
Plate resistance
400000 Ω
Transconductance
0.00138 S
Amplification factor
550
Max plate voltage
250 V
Max screen voltage
90 V

Representative characteristics at plate 180 V, screen 75 V, grid -1.5 V. Maximum operating table includes 250 V plate and 90 V screen.

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

2026 Western Electric 200s

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Capacitance

  • ControlGridToPlateCapacitance

    0.004 pF

  • ControlGridToHeaterCathodeScreenCapacitance

    5.8 pF

  • PlateToHeaterCathodeScreenCapacitance

    14 pF

Other

  • Maximum Heater Cathode Voltage

    90 V

  • Screen Grid Current

    1.2 mA

    PlateVoltage=180V;ScreenVoltage=75V;GridBias=-1.5V

  • Plate Current

    5.5 mA

    PlateVoltage=180V;ScreenVoltage=75V;GridBias=-1.5V