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Power - Pentode (NOT beam) ·Pentode

7591S

Power/output pentode designed for low-frequency or audio-frequency output amplification.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
IO
Base pins
8
Nominal heater
6.3 V / 800 mA

Description

The source identifies this device as 7591S power pentode.

Socket description

International Octal

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
IO
Base pins
8
Nominal heater voltage
6.3 V
Nominal heater current
800 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

1 physical section, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
29000 Ω
Transconductance
0.01 S
Amplification factor
16.8
Max plate voltage
550 V
Max screen voltage
440 V
Max plate dissipation
19 W
Max screen dissipation
3.3 W
Max cathode current
85 mA

Power pentode with Class A1 typical characteristics.

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

199X JJ

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Typical Plate Voltage

    300 V

  • Typical Screen Voltage

    300 V

  • TypicalControlGridVoltage

    -10 V

  • Typical Plate Current

    60 mA

  • Typical Screen Current

    8 mA

Characteristic

  • GridCapacitance

    10 pF

  • Plate Capacitance

    5 pF

  • PlateGridCapacitance

    0.25 pF

Data set 02

2026 JJ Electronic

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Uf

    6.3 V

    Published value

  • If

    800 mA

    Published value

  • Ua

    550 V

    Published value

  • Ug2

    440 V

    Published value

  • Wa

    19 W

    Published value

  • Wg2

    3.3 W

    Published value

  • Ik

    85 mA

    Published value

  • Rg1

    0.3 MΩ

    Published value

  • Ukf

    200 V

    Published value

Characteristics

  • Ua

    300 V

    Published value

  • Ug2

    300 V

    Published value

  • Ug1

    -10 V

    Published value

  • Ia

    60 mA

    Published value

  • Ig2

    8 mA

    Published value

  • S

    10000 µS

    Published value

  • µ

    16.8

    Published value