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Power - Pentode (NOT beam) ·Pentode

1LB4

Power/output pentode designed for Class-A, single-ended, or push-pull audio-frequency output amplification.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
5AD
Socket code
B8G
Base pins
8
Nominal heater
1.4 V / 50 mA

Description

1LB4 is listed as a power-amplifier pentode in the supplied receiving-tube handbook. It uses a 1.4 V, 0.05 A directly heated filament. The handbook publishes maximum ratings and representative operating characteristics for its intended service.

Socket description

Loctal 8-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
5AD
Socket code
B8G
Base pins
8
Nominal heater voltage
1.4 V
Nominal heater current
50 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

5AD - 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
250000 Ω
Transconductance
0.000925 S
Max plate voltage
110 V
Max screen voltage
110 V
Max cathode current
6 mA

Source states ratings/electrical characteristics identical to pentode section of 1D8GT and reproduces key values.

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 General Electric Essential Characteristics

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Maximum plate voltage

    110 V

    Published handbook rating

  • Maximum screen voltage

    110 V

    Published handbook rating

  • Plate voltage

    90 V

    ClassA

  • Screen voltage

    90 V

    ClassA

  • Control-grid voltage

    -9 V

    ClassA

  • Plate current

    5 mA

    ClassA

  • Screen current

    1 mA

    ClassA

  • Load resistance

    112000 ohm

    ClassA

  • Power output

    0.2 W

    ClassA

Characteristic

  • Plate resistance

    250000 ohm

    Published handbook characteristic

  • Transconductance

    925 µS

    Published handbook characteristic

  • Filament voltage

    1.4 V

    DirectlyHeated DC filament

  • Filament current

    50 mA

    DirectlyHeated DC filament