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Voltage Pentode ·Pentode

EF804S

Long-life low-hum, low-noise audio pentode for sensitive professional low-level amplifier service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B9A
Base pins
9
Nominal heater
6.3 V / 170 mA

Description

Long-life low-hum low-noise AF pentode.

Socket description

Small-button Noval 9-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B9A
Base pins
9
Nominal heater voltage
6.3 V
Nominal heater current
170 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
2000000 Ω
Transconductance
0.002 S
Max plate voltage
300 V
Max screen voltage
200 V
Max plate dissipation
1 W
Max screen dissipation
0.2 W
Max cathode current
6 mA

Published Telefunken values promoted where applicable; additional values retained as parameters.

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

1953 AEG

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Typical Plate Voltage

    250 V

  • Typical Screen Voltage

    140 V

  • Typical Plate Current

    3.2 mA

  • Typical Screen Current

    0.6 mA

Capacitance

  • Input Capacitance

    4.3 pF

  • Output Capacitance

    5.5 pF

Data set 02

1959 Telefunken

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristics

  • Low-noise design

    Yes

Application

  • Triode-connected operation

    Published

    TriodeConnection