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

E81L

Special-quality long-life power/output pentode designed for stable professional, industrial, or wideband amplifier service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
Noval
Socket code
B9A
Base pins
9
Nominal heater
6.3 V / 375 mA

Description

E81L is listed in the supplied Amperex material as a premium-quality power pentode. Published ratings and characteristics were captured from the supplied table.

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
Noval
Socket code
B9A
Base pins
9
Nominal heater voltage
6.3 V
Nominal heater current
375 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

Noval - 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
300000 Ω
Transconductance
0.011 S
Max plate voltage
210 V
Max screen voltage
210 V
Max plate dissipation
4.5 W
Max screen dissipation
1.2 W
Max cathode current
30 mA

Long-life output pentode ratings from shared source sheet.

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

  • Plate voltage

    210 V

  • Screen-grid voltage

    210 V

  • Cathode resistance

    120 Ω

  • Plate current

    20 mA

  • Screen-grid current

    5.3 mA

  • Cold plate voltage maximum

    550 V

  • Cold screen-grid voltage maximum

    550 V

Characteristic

  • Transconductance

    11 mA/V

  • Equivalent noise resistance

    1.2 kΩ

  • Voltage gain, preamplifier

    175

    Preamplifier

Data set 02

1958 Amperex Industrial

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Maximum plate voltage

    210 V

    Published table

  • Plate voltage

    210 V

    Published table

  • Screen voltage

    210 V

    Published table

  • Plate current

    30 mA

    Published table

  • Power output

    36 W

    Published table

Characteristic

  • Plate resistance

    11000 ohm

    Published table

  • Heater/filament voltage

    6.3 V

    Published rating

  • Heater/filament current

    375 mA

    Published rating

Data set 03

1958 Mullard Receiving Tubes

Published operating points and test conditions from this source.

SECTION 1

Pentode

Application

  • Application

    Telephone-equipment output amplifier

Data set 04

1963 Amperex Condensed

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • Heater voltage

    6.3 V

    Published rating

  • Heater current

    375 mA

    Published rating

  • Published characteristic value

    11.5

    PremiumQuality

  • Published characteristic value 2

    6.5

    PremiumQuality

Other

  • Maximum plate voltage

    210 V

    PremiumQuality

  • Plate voltage

    210 V

    PremiumQuality

  • Plate current

    30 mA

    PremiumQuality

Data set 05

1963 Philips Electron Tubes Handbook V1a

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate voltage

    210 V

  • Screen voltage

    210 V

  • Plate current

    20 mA

  • Screen current

    5.3 mA

  • Output power

    1 W

    Output

Characteristic

  • Transconductance

    11000 uS

  • Plate resistance

    0.3 MOhm

Data set 06

1963 Philips Electron Tubes Handbook V3

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • Heater voltage

    6.3 V

    Published heater rating

  • Heater current

    375 mA

    Published heater rating

  • Transconductance

    11000 µS

    Published characteristic point

  • Plate resistance

    300000 ohm

    Published characteristic point

  • Amplification factor

    36

    Published characteristic point

Other

  • Plate voltage

    210 V

    Published characteristic point

  • Screen voltage

    210 V

    Published characteristic point

  • Plate current

    20 mA

    Published characteristic point

  • Screen current

    5.3 mA

    Published characteristic point

Data set 07

1999 Philips E-Z

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • Life test

    10000 h

    Published datasheet value

  • Heater voltage Ve

    6.3 V

    Published datasheet value

  • Heater current I

    375 mA

    Published datasheet value

  • Anode current I,

    20 mA

    Published datasheet value

  • Heater current I

    395 mA

    Published datasheet value

  • Grid No

    0 V

    Published datasheet value

  • Grid No

    210 V

    Published datasheet value

  • Grid No

    3.1 mA

    Published datasheet value

  • Internal resistance R

    0.2 MQ

    Published datasheet value

  • heater Vif =

    120 V

    Published datasheet value

  • cathode heater and screen Cg,/ kis |

    14.3 pF

    Published datasheet value

  • I =

    25 mA

    Published datasheet value

  • Cathode to heater Cis

    4.2 pF

    Published datasheet value

  • The tube is subjected during

    32 h

    Published datasheet value

  • under the following conditions during

    10 h

    Published datasheet value

  • Anode voltage Vao max

    550 V

    Published datasheet value

  • Va max

    210 V

    Published datasheet value

  • Anode dissipation Wy max

    4.5 W

    Published datasheet value

  • Grid No

    550 V

    Published datasheet value

  • Vgz max

    210 V

    Published datasheet value

  • Grid No

    1.2 W

    Published datasheet value

  • Cathode current Iy max

    30 mA

    Published datasheet value

  • automatic bias Rgl max

    0.5 MQ

    Published datasheet value

  • fixed bias Rgl max

    0.25 MQ

    Published datasheet value

  • Voltage between cathode and heater Vs max

    120 V

    Published datasheet value

  • Heater voltage: The average heater voltage should be

    6.3 V

    Published datasheet value

  • heater voltage exceeding the range of

    6.6 V

    Published datasheet value

  • Anode current Iy

    20 mA

    Published datasheet value

  • Grid No

    5.3 mA

    Published datasheet value

  • Anode current I

    15 mA

    Published datasheet value

  • Grid No

    4 mA

    Published datasheet value

  • Vp =

    210 V

    Published datasheet value

  • Vo3=

    0 V

    Published datasheet value

  • (oF) Uy =

    210 V

    Published datasheet value

  • Vp3=

    0 V

    Published datasheet value

  • (mA)

    3 V

    Published datasheet value

  • ] —

    5 V

    Published datasheet value

  • y v

    6 V

    Published datasheet value