Skip to main content
Tube Tinker — Electron Tube Database
Alternatives & variationsDownload PDF datasheet

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

EL42

Low-heater-current output pentode designed particularly for automobile-radio audio stages.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
B8A
Socket code
B8A
Base pins
8
Nominal heater
6.3 V / 200 mA

Description

OUTPUT PENTODE Output pentode with an anode dissipation of6W, suitable for use in cor radio receivers. EL42 Th e limit ing values. charact e rist ics and audio perfor mance of t he EL42 and EL85 ar e iden ti cal. Th e basing and dim e nsions of t he EL42 ar e show n below. o ~ ) I ~

Socket description

Rimlock 8-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
B8A
Socket code
B8A
Base pins
8
Nominal heater voltage
6.3 V
Nominal heater current
200 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

B8A - 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
90000 Ω
Transconductance
0.0032 S
Amplification factor
288
Max plate voltage
300 V
Max screen voltage
300 V
Max plate dissipation
6 W
Max screen dissipation
3.3 W

Published ratings/characteristics promoted from the approved source.

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

1951 Mullard Valve and Service Manual

Published operating points and test conditions from this source.

SECTION 1

Pentode

Application

  • Service

    Audio power output

Data set 02

1953 La Radiotechnique

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • HeaterVoltageNominal

    6.3 V

    Nominal

  • HeaterCurrentNominal

    200 mA

    Nominal

  • Maximum Plate Voltage

    300 V

  • Maximum Screen Voltage

    300 V

  • Maximum Plate Dissipation

    6 W

Characteristic

  • Transconductance

    3200 µS

    Typical

  • Amplification Factor

    288

    Typical

  • Plate Resistance

    90000 ohm

    Typical

Data set 03

1963 Philips Electron Tubes Handbook V1a

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • Heater voltage

    6.3 V

    Published heater rating

  • Heater current

    700 mA

    Published heater rating

  • Transconductance

    3200 µS

    ClassA

  • Plate resistance

    90000 ohm

    ClassA

Other

  • Plate voltage

    225 V

    ClassA

  • Screen voltage

    225 V

    ClassA

  • Plate current

    26 mA

    ClassA

  • Screen current

    4.1 mA

    ClassA

  • Load resistance

    9000 ohm

    ClassA

  • Push-pull power output

    7 W

    ClassAB PushPull TwoTubes

Data set 04

1967 Mullard Receiving Tubes for Maintenance

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • Output pentode roted for

    6

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • up (

    120 a

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • gm

    3.1 mA

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • ra

    100

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

Other

  • Va

    250 V

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • EL8S Output pentode rated for

    6 W

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • up to

    120 a

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • Vg•

    250 V

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • Va

    300 V

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • Vg •

    175 V

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • Vg,

    30 V

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • Vg J

    -60 V

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • Vg1

    -100 V

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • Output pentode rated for

    6 W

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • VaIn) max

    550 V

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • Va max

    300 V

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • Vg

    550 V

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • Vg

    300 V

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • Vg

    100 V

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • Vg1 ma x . (lg1 = +

    1.3 ma

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • EL8S Output pentode rated for

    6

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • up to

    120 a

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • I.V o " Vg

    250 V

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

  • 2.Vo = Vg 2 = 200V

    200

    Published EL85 value; supplied EL42 sheet states electrical characteristics are identical.

Data set 05

1999 Philips E-Z

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • Chauffage: indirect par C.C. Ve

    6.3 V

  • Wo = 2,1

    2.8 W

  • Vi{Wo

    50 mW

  • Wo = 0 0,05 4,1 0 0,05

    7 w

  • Igz = 2x0,8 - 2x%4,6 2x0,8

    ~ 2x6.5 mA

  • Wo = 0 QoS5 4 0 005

    6.5 W

  • va 9

    200 V

  • PHILIPS

    6 W

Capacitance

  • Capacités c

    6.2 pF

  • Cag1

    < 0.2 pF

  • Cg1f

    < 0.2 PF

Other

  • Va = 200

    225 V

    ClassA

  • Vg2 = 200

    225 V

    ClassA

  • Ia = 22,5

    26 mA

    ClassA

  • Ig2 = 3,5

    4.1 mA

    ClassA

  • s = 3,2

    3.2 mA/V

    ClassA

  • Va = 200

    250 v

    ClassA

  • Vgz = 200

    250 v

    ClassA

  • 1a = 2x16 - 2x17 2x20

    2x21.5 mA

    ClassA

  • Igp = 2x2,6 - 2x5,6 2x3,2

    2x6.7 mA

    ClassA

  • v, = 200

    250 v

    ClassB

  • Va2 200

    250 v

    ClassB

  • Vg1 = =17

    -22.5 v

    ClassB

  • Ia = 2x5 - 2x16 2x5

    2x20 mA

    ClassB

  • Grenzdaten Vao = max

    550 V

  • Va = max.,

    300 V

  • VgQO = max

    550 V

  • Vg? = max

    300 V

  • Wg2(V3i=0) = max

    1 W

  • Wgg(wozmax.) = max

    2 W

  • Ix = max

    35 mA

  • Vg1(Ig1=+O, [1]

    3 uA

  • Vg1(Ig1=+O, [2]

    -1.3 V