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Power - Pentode (NOT beam) ·Pentode

EL503

High-transconductance power pentode for sensitive, high-current audio-frequency output stages.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
9C18
Socket code
B9D
Base pins
9
Nominal heater
6.3 V / 1.05 A

Description

Power pentode for AF output amplification. Indirectly heated Mazda/Belvu receiving tube; descriptive text translated to English from the French source.

Socket description

Magnoval 9-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
9C18
Socket code
B9D
Base pins
9
Nominal heater voltage
6.3 V
Nominal heater current
1.05 A
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

9C18 - 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
7700 Ω
Transconductance
0.023 S
Max plate voltage
300 V
Max screen voltage
300 V
Max screen dissipation
6 W
Max cathode current
200 mA

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

1968 Mazda Belvu

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Tension filament vf

    63 V

  • Courant filament … Îf

    12 A

  • Tension d'anode, à courant nul …………….….…. Vabl

    550 V

  • Tension d'anode ... —… Va

    300 V

  • Tension de grille n°2, à courant nul … Vg bl

    550 V

  • Tension de grille n°2 ... … Ve

    300 V

  • Dissipation de grille n°2 … Pg

    6 W

  • Dissipation de crète de gulle n° 2 … Pg,cer

    9 W

  • Courant de cathode …… … IK

    200 mA

  • Tension entre le filament et la cathode …… VIK

    100 V

Characteristic

  • Capacité d'entré@ ………mseenenennnnnnnnnnns Ce

    22.5 pF

  • Capacité grille n° 1/anode ……s Cg,/ à

    2.2 pF

  • Capacité de@ SOrti® ……s Cs

    12.6 pF

  • Tension d'Anod@ ….…..….….…….cerercesrerereene VA

    250 V

  • Tension de grille n°2... … Ve

    250 V

  • Tension de grille n°oi…. … Veg,

    -13.2 V

  • Courant d'anod@e ……n I

    100 mA

  • Courant de grille n°2 ...c TB2

    8.5 mA

  • Pente …… … 8

    23 mA

  • Tension d'alimentation d'anode ……………. VaN

    265 V

  • Tension d'alimentation de grille n°02 …. VgN

    265 V

  • Courant d'Anod@e ……...….….….……rererierencernc. IA 2x100 | 2x1

    18 mA

  • Courant de grille n°2 ...c 182 2x8,5 | 2x3

    2.5 mA

  • Puissance de sortie . Ps 0

    40 W

  • (mA) Pa=

    27 W

  • 27W V% ; —

    -2.5 V

  • 600 e x

    -5 V

  • P -]

    2.5 V

Data set 02

1972 Philips Receiving Tubes

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristics

  • Heater voltage

    6.3 V

    Published nominal value

  • Heater current

    1.05 A

    Published nominal value

  • Transconductance

    23000 µS

    Published or referenced operating characteristic

  • Transconductance

    23 mA/V

    Published quick-reference value

Other

  • Audio output power

    40 W

    ClassAB, published quick-reference value

Data set 03

1999 Philips E-Z

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Quick-reference anode current

    110 mA

  • Output power

    40 W

    ClassAB

Characteristic

  • Anode to grid-1 capacitance

    1.7 pF

  • Grid-1 to heater capacitance

    0.325 pF