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Voltage Pentode - Remote Cutoff (single) ·Pentode

UF41

Variable-mu voltage pentode for gain-controlled RF and IF amplification in low-current series-heater receivers.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B8A
Base pins
8
Nominal heater
12.6 V / 100 mA

Description

Variable-mu voltage pentode for radio-frequency or intermediate-frequency amplification. The supplied French datasheet was translated to English for descriptive output.

Socket description

Rimlock 8-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B8A
Base pins
8
Nominal heater voltage
12.6 V
Nominal heater current
100 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
600000 Ω
Transconductance
0.0022 S
Max plate voltage
250 V
Max screen voltage
250 V
Max plate dissipation
2 W
Max screen dissipation
0.3 W
Max cathode current
10 mA

Variable-gain/remote-cutoff pentode; promoted characteristics use the fixed-screen 100 V nominal operating point.

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 La Radiotechnique

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate Voltage

    100 V

    FixedScreen

  • Screen Voltage

    100 V

    FixedScreen

  • Grid Voltage

    -2.5 V

    FixedScreen

  • Plate Current

    6 mA

    FixedScreen

  • Screen Current

    1.75 mA

    FixedScreen

Capacitance

  • InputCapacitanceCold

    5.3 pF

    Cold

  • Output Capacitance

    7 pF

    Cold

  • Plate To Grid Capacitance

    0.002 pF

    Maximum

  • InputCapacitanceHot

    6.6 pF

    Hot

Data set 02

1957 Philips Receiving and Amplifying Tubes

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate Voltage

    170 V

  • Plate Current

    6 mA

  • Screen Voltage

    120 V

  • Screen Current

    1.75 mA

Characteristic

  • Transconductance

    2300 µS

  • Plate Resistance

    1000000 ohm

Data set 03

1963 Philips Electron Tubes Handbook V1

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate voltage

    170 V

    RF/IF amplifier

  • Screen voltage

    100 V

    RF/IF amplifier

  • Plate current

    6 mA

    RF/IF amplifier

  • Screen current

    1.75 mA

    RF/IF amplifier

  • Maximum plate voltage

    250 V

  • Maximum screen voltage

    250 V

  • Maximum plate dissipation

    2 W

Characteristic

  • Transconductance

    2200 uS

  • Plate resistance

    1 Mohm

Data set 04

1967 Mullard Receiving Tubes for Maintenance

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • I~ 3.3 6.0

    7.2 mA

    Published in approved UF41.pdf target datasheet; Section1

  • 1. 2 1.0 1.75

    2.1 mA

    Published in approved UF41.pdf target datasheet; Section1

  • gill 1.9 2.2

    2.3 mA

    Published in approved UF41.pdf target datasheet; Section1

  • Vg 2 max. (1. ·<

    4 mA

    Published in approved UF41.pdf target datasheet; Section1

  • Vg 2 max . (l a =

    7.2 mA

    Published in approved UF41.pdf target datasheet; Section1

  • I k max

    10 mA

    Published in approved UF41.pdf target datasheet; Section1

Data set 05

1968 Mazda Belvu

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Tension filament ….………rrrererereenenmnennnennneÜO VÉ

    12.6 V

  • Courant filament ….….…..….….…eecresrseeesesnseeseu. IË

    100 mA

  • Capacité anode/ grille n° 1. mn Ca/ 81

    2 mpF

  • Capacité grille n° 1/ filament …… CE1/f

    0.1 pF

  • Tension d'anode à courant nul …… Vabl

    550 V

  • Tension d'anode ……c … Va

    250 V

  • Tension de grille n°2 à courant nu1 … Vg,bl

    550 V

  • Tension de grille n° 2 pour Ia<4 mA … … Ve

    250 V

  • pour Ia=7,2 mA …………. Veg

    150 V

  • Dissipation de grille n°2 ... Pg

    0.3 W

  • sesvacscenasenee ÎK

    10 mA

  • grille de + 0,3 HA ……urceccrareremnessecericorcencou- VE

    1.3 V

  • Tension entre filament et cathode …… Vfk

    150 V

Capacitance

  • Capacité d'entrée ….…..….…sumimmmimnmnennn.s Ce

    4.9 pF

  • Capacité de sortie ……… . Cs

    5.7 pF

Characteristic

  • Tension d'alimentation ……c VN

    100 V

  • Tension d'AnOd@ ….…....…eeererercrorecscercecence VA

    100 V

  • Tension de grille n° 2 … … Ve

    100 V

  • Résistance de cathode … . Rk

    325 Ω

  • Tension de grille n°1 … … Ve; -2,55

    -16.55 V

  • Pente …… .S 2,2

    0.022 mA

  • Résistance 1nterne … p 0,6 >

    10 mΩ

Data set 06

1999 Philips E-Z

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristics

  • Capacitznces Cg

    5.7 a

    Capacitznces Cg = 5,7 pF