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Voltage - Triode (under 100V) ·Triode

EM4

Electrometer triode designed for input stages of precision electrometer instruments measuring extremely small electrical currents.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
P8A
Base pins
-
Nominal heater
1.3 V / 24 mA

Description

Electrometer triode for input stages of various electrometer devices.

Socket description

European 8-pin side-contact base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
P8A
Base pins
-
Nominal heater voltage
1.3 V
Nominal heater current
24 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

Triode

X-ray radiationInterelectrode capacitances
Transconductance
0.00008 S
Amplification factor
2.2
Max plate voltage
10 V
Max cathode current
0.5 mA

Promoted ratings and characteristics are taken from the printed target-tube entry in the approved PDF.

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

1981 Russian Tubes Katsnelson and Larionov

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Heater voltage

    1.3 V

    Published nominal/basic-parameter heater condition.

  • Heater current

    24 mA

    Published heater current.

  • Plate current

    0.2 mA

    Published basic-parameter operating point.

  • Transconductance

    80 µS

    Published basic-parameter value; normalized to µS.

  • Amplification factor

    2.2

    Published amplification factor.

  • Grid current

    0.000007 mA

    Published in the filename-designated tube entry.

  • Free-grid potential

    -1.4 V

    Published in the filename-designated tube entry.

  • Service life

    2500 h

    Published in the filename-designated tube entry.

Other

  • Maximum plate voltage

    10 V

    Published limiting operating value.

  • Maximum cathode current

    0.5 mA

    Published limiting cathode-current value.

Data set 02

1999 Philips E-Z

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Published electrical datum

    250 V

    daBB bei 0 Volt Gltterspannung (flll' 250 V Kurve a: Kennli.ni.edes.unempfi"ndlichcnTeiles.dcrEMAl-.

  • Published electrical datum

    -

    ,empfindlichen” Steges - J§An3 A

  • Published electrical datum

    -

    auf 5° gesunken, wih- 5wt A P H L

  • Published electrical datum

    250 V

    strom Is als Funktion der Gittersy g bei einer Speisespannung von 250 V.

  • Published electrical datum

    -

    Station die Gleichspannung von —10 bis —15 Volt #indert, so findet man fiir Kurve a

  • Published electrical datum

    -

    50F++ A HTst |- 1 teristik ghnlich der

  • Published electrical datum

    30 V

    =30 V() -25 -20 -15 -10 -5 0 schwache wie auch

  • Published electrical datum

    200 V

    von 200 V. Empfindlichkeits-

  • Published electrical datum

    100 V

    nung von 100 V.

  • Published electrical datum

    5 V

    —16 bzw. —5 V Gitterspannung sehr flach zu verlaufen anfangen. Es bleiben restliche

  • Published electrical datum

    6.3 V

    Heizspannung von 6,3 V wie bei Serienspeisung mit einem Heizstrom von 200 mA

  • Published electrical datum

    100 V

    verwendet werden kann, In G/W-Geriiten mit einer Spannung von 100 V ist die Helligkeit

  • Published electrical datum

    63 V

    Heizspanmung . . . . « + v v o v v v v o v v v v v o . ¥y 63 V

  • Published electrical datum

    0 v

    . . . . ¢ v v v v v v v v 0 v 0 v B1 0,200

  • Published electrical datum

    0 V

    Schirmstrombei V; = 0V . . . (Vg

  • Published electrical datum

    0 V

    =0V) = 0,2 mA 0,55 mA 0,75 mA

  • Published electrical datum

    0 V

    teiles . . ... .0 V(e =90°) =0V (% ("

  • Published electrical datum

    -

    Der Abstimmanzeiger EM 4 kann in allen Wechselstrom- oder G/W-Geriten mit

  • Published electrical datum

    2.5 MQ

    fiic den Fall, daB dieser 1 bzw. 2,5 MQ betriigt (strichpunktierte und gestrichelte

  • Published electrical datum

    -

    Fiir G/W-Gerite, die ausschlieBlich bei 100 Volt arbeiten, besteht noch die Moglichkeit,

  • Published electrical datum

    100 V

    spannung von 100 V, wenn dem

  • Published electrical datum

    1 MQ

    widerstand von 1 MQ,

  • Published electrical datum

    2.5 MQ

    von 2,5 MQ.

  • Published electrical datum

    0 V

    von 0 V ist die Steilheit groBer woraus sich auch eine gréBere Anzeigeempfindlichkeit

  • Published electrical datum

    100 V

    5L i, ot einer Speisespannung von 100 V,

  • Published electrical datum

    1 MQ

    Widerstand von 1 MQ gespeist

  • Published electrical datum

    2.5 MQ

    L o 2,5 MQ geschaltet.

Other

  • Published electrical datum

    550 V

    Vao o« ¢« « o . . = max. 550 V 2 = max. 275 V

  • Published electrical datum

    275 V

    Va = max. 275 V Vg Iy= + 0,3 pA). = max. —1,3 V

  • Published electrical datum

    550 V

    Vago + + + « « . . = max. 550 V Rep . . . . . . . .. = max. 3 MQ

  • Published electrical datum

    275 V

    as = max. 275 V Rep . . . . . o .. . = max. 20.000 Q

  • Published electrical datum

    550 V

    S0 . . . - . = max. 550 V Vik o o o v v o o = max. 100 V1)

  • Heater voltage

    6.3 V

    Nominal heater rating

  • Heater current

    200 mA

    Nominal heater rating