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Power - Pentode (NOT beam) ·Pentode

6A4

Directly heated audio power pentode for automobile and receiver output stages, usable singly or in push-pull.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
5B
Socket code
UY5
Base pins
5
Nominal heater
6.3 V / 300 mA

Description

Directly heated output pentode intended especially for DC operation and automobile receivers, usable singly or in push-pull output stages.

Socket description

Medium 5-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
5B
Socket code
UY5
Base pins
5
Nominal heater voltage
6.3 V
Nominal heater current
300 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

5B - 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
45400 Ω
Transconductance
0.0022 S
Amplification factor
100
Max plate voltage
180 V
Max screen voltage
180 V
Max cathode current
26 mA

Published maximum ratings and representative operating characteristics reviewed.

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

1940 RCA

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • HeaterVoltageNominal

    6.3 V

    Nominal

  • HeaterCurrentNominal

    300 mA

    Nominal

  • Maximum Plate Voltage

    180 V

  • Maximum Screen Voltage

    180 V

  • Maximum Cathode Current

    26 mA

Characteristic

  • Transconductance

    2200 µS

    Typical

  • Amplification Factor

    100

    Typical

  • Plate Resistance

    453500 ohm

    Typical

Data set 02

1950 Sylvania

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • Plate Resistance

    60000 ohm

  • Transconductance

    2500 µS

  • Amplification Factor

    150

Other

  • Maximum Plate Voltage

    180 V

  • Maximum Screen Voltage

    180 V

  • Power Output

    1.5 W

  • Load Resistance

    8000 ohm

Data set 03

195X General Electric Essential Characteristics

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Maximum plate voltage

    180 V

    Published handbook rating

  • Maximum screen voltage

    180 V

    Published handbook rating

  • Plate voltage

    180 V

    ClassA

  • Screen voltage

    180 V

    ClassA

  • Control-grid bias

    12 V

    ClassA

  • Plate current

    22 mA

    ClassA

  • Screen current

    3.9 mA

    ClassA

  • Load resistance

    8000 ohm

    ClassA

  • Power output

    1.4 W

    ClassA

Characteristic

  • Plate resistance

    45400 ohm

    Published handbook characteristic

  • Transconductance

    2200 µS

    Published handbook characteristic

  • Heater/filament voltage

    6.3 V

    Published heater/filament rating

  • Heater/filament current

    300 mA

    Published heater/filament rating