EL12

Power/output pentode designed for audio-frequency power amplification in single-ended or push-pull output stages.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: -
Socket code: Y8A
Base pins: 8
Nominal heater: 6.3 V / 1.2 A

Description

High-power audio output pentode for single-ended class-A and push-pull class-AB service.

Socket description

Steel-tube 8-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: -
Socket code: Y8A
Base pins: 8
Nominal heater voltage: 6.3 V
Nominal heater current: 1.2 A
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: 50000 Ω
Transconductance: 0.015 S
Max plate voltage: 350 V
Max screen voltage: 350 V
Max plate dissipation: 18 W
Max screen dissipation: 2.8 W
Max cathode current: 120 mA

Published ratings and characteristics promoted where clearly stated; identical repeated sections compressed where applicable.

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 RFT Rundfunk Technik

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

HeaterVoltageNominal
6.3 V
Nominal
HeaterCurrentNominal
1.2 A
Nominal
Maximum Plate Voltage
350 V
Maximum Screen Voltage
350 V
Maximum Plate Dissipation
18 W
Maximum Screen Dissipation
2.8 W
Maximum Cathode Current
120 mA

Characteristic

Transconductance
12000 µS
Typical
Plate Resistance
50000 ohm
Typical

Data set 02

1959 Telefunken

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

Plate voltage
250 V
ClassA;SingleEnded
Screen-grid voltage
250 V
ClassA;SingleEnded
Plate current
72 mA
ClassA;SingleEnded
Screen-grid current
8 mA
ClassA;SingleEnded
Load resistance
3500 Ohm
ClassA;SingleEnded
Output power
8 W
ClassA;SingleEnded
Plate voltage
350 V
ClassAB;PushPull;TwoTubes
Screen-grid voltage
350 V
ClassAB;PushPull;TwoTubes
Cathode resistor
250 Ohm
ClassAB;PushPull;PerTube
Plate-to-plate load resistance
5000 Ohm
ClassAB;PushPull;TwoTubes
Plate cold voltage
650 V
Screen-grid cold voltage
650 V

Capacitance

Grid-to-plate capacitance maximum
0.7 pF

Data set 03

1999 Philips E-Z

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

Capacities Cagl
< 0.7 pF
Ig2
8 mA
ClassA
Vo (dyop = 10%)
8 W
Vi (dtot = 10%)
4.5 V
Vi (Wo [1]
50 mW
Vi (Wo [2]
0.3 V

Other

Va
250 V
ClassA
Vg2
250 V
ClassA
Vel
<71 V
ClassA
Ta
72 mA
ClassA
Va
250 v
ClassA
Vg2
250 v
ClassA
Ia = 2x45
2x53 mA
ClassA
Ig2 = 2x5,1
2x8.5 mA
ClassA
Wo = 0
14.5 w
ClassA
Va, =max [1]
550 V
Va, =max [2]
0 V
Va, =max [3]
2.5 W
Va =max [1]
250 V
Va =max [2]
5 W
Wa =max [1]
18 W
Wa =max [2]
0.3 uA
Wa =max [3]
-1.3 V
Vg2o =max
550 V
Vg2 =max
275 V
Ik =max [1]
90 mA
Ik =max [2]
950 V