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Voltage Pentode or Tetrode (under 100V) ·Diode-Pentode

1U5WA

Ruggedized diode-pentode for detector and voltage-amplifier service in portable or specialized battery equipment. The diode supplies signal detection while the comparatively strong pentode provides subsequent gain with low filament demand.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
-
Socket code
B7G
Base pins
7
Nominal heater
1.25 V / 50 mA

Description

Ruggedized filament-type diode-pentode for detection, AVC rectification, and audio-frequency amplification in portable receivers.

Socket description

Miniature 7-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B7G
Base pins
7
Nominal heater voltage
1.25 V
Nominal heater current
50 mA
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

2 physical sections, each with unique specifications.

Section 1

Diode

X-ray radiationInterelectrode capacitances
Max plate voltage
90 V
Max cathode current
1 mA
Rectifier nominal output current
1 mA

Published maximum ratings and characteristics promoted from approved source.

Section 2

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
650000 Ω
Transconductance
0.0012 S
Max plate voltage
90 V
Max screen voltage
67.5 V
Max plate dissipation
0.17 W
Max screen dissipation
0.035 W
Max cathode current
2.5 mA

Published maximum ratings and characteristics promoted from 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

1938 Raytheon

Published operating points and test conditions from this source.

SECTION 1

Diode

Other

  • HeaterVoltageNominal

    1.25 V

    Nominal

  • HeaterCurrentNominal

    50 mA

    Nominal

  • Maximum Plate Voltage

    90 V

  • Maximum Cathode Current

    1 mA

SECTION 2

Pentode

Other

  • HeaterVoltageNominal

    1.25 V

    Nominal

  • HeaterCurrentNominal

    50 mA

    Nominal

  • Maximum Plate Voltage

    90 V

  • Maximum Screen Voltage

    90 V

  • Maximum Plate Dissipation

    0.17 W

  • Maximum Cathode Current

    2.5 mA

Characteristic

  • Transconductance

    550 µS

    Typical

Data set 02

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Diode

Other

  • Heater voltage

    1.25 V

    Nominal

  • Heater current

    50 mA

    Nominal

SECTION 2

Pentode

Other

  • Heater voltage

    1.25 V

    Nominal

  • Heater current

    50 mA

    Nominal

Data set 03

1966 Tung Sol Electronic Tubes 3 of 4

Published operating points and test conditions from this source.

SECTION 1

Diode

Other

  • Maximum impact acceleration

    450 G

    Ruggedized

  • Maximum vibrational acceleration

    2.5 G

    Ruggedized

  • Nominal filament voltage

    1.25 V

  • Filament current

    50 mA

Characteristic

  • Average diode current

    1 mA

    DetectorService

SECTION 2

Pentode

Other

  • Plate voltage

    67.5 V

    Typical

  • Grid #2 voltage

    67.5 V

    Typical

Characteristic

  • Transconductance

    650 uS