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Power - Pentode Single (NOT beam) (under 10W) ·Pentode

EL71

Low-voltage audio power pentode providing approximately 1 W from only a 100 V plate supply.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
B8D/F
Socket code
WIRE8
Base pins
8
Nominal heater
6.3 V / 450 mA

Description

Subminiature audio output pentode. Published heater, characteristics, ratings and application information were read from the supplied Mullard sheet.

Socket description

Subminiature all-glass 8-wire lead family

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
B8D/F
Socket code
WIRE8
Base pins
8
Nominal heater voltage
6.3 V
Nominal heater current
450 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

B8D/F - 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
15000 Ω
Transconductance
0.0042 S
Max plate voltage
165 V
Max screen voltage
155 V
Max plate dissipation
4 W
Max screen dissipation
1 W
Max cathode current
50 mA

Published characteristics and absolute ratings.

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

1958 Mullard Receiving Tubes

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristics

  • Plate voltage

    100 V

  • Screen-grid voltage

    100 V

  • Plate current

    30 mA

  • Screen-grid current

    1.2 mA

Other

  • Output power

    1 W

    SingleEnded

Data set 02

1963 Mullard

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • Anode current

    30 mA

    Va=100V; Vg2=100V

  • Screen current

    1.2 mA

    Va=100V; Vg2=100V

Other

  • Load resistance

    3000 ohm

    Typical

  • Output power

    1 W

    Typical