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Tuning Indicator ·Triode-TuningIndicator

EM84

Magic-band tuning indicator with integral triode amplifier and elongated fluorescent display whose illuminated length indicates receiver tuning or signal level.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
Noval
Socket code
B9A
Base pins
9
Nominal heater
6.3 V / 210 mA

Description

Tuning indicator with integral triode amplifier. Indirectly heated Mazda/Belvu receiving tube; descriptive text translated to English from the French source.

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
210 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

2 physical sections, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Max plate voltage
300 V
Max plate dissipation
0.5 W

Published section ratings and characteristics promoted where applicable.

Section 2

Tuning Indicator

X-ray radiationInterelectrode capacitances
Max plate voltage
300 V
Max plate dissipation
0.5 W
Max cathode current
3 mA

Published section ratings and characteristics promoted 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 La Radiotechnique

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater voltage

    6.3 V

    Published nominal value

  • Heater current

    210 mA

    Published nominal value

Data set 02

195X Tesla

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater voltage

    6.3 V

    Published nominal value

  • Heater current

    210 mA

    Published nominal value

Data set 03

1963 Amperex Condensed

Published operating points and test conditions from this source.

SECTION 2

Tuning Indicator

Other

  • Plate and target supply voltage

    250 V

    TuningIndicator

  • Target current

    1.1 mA

    TuningIndicator

  • Series resistance

    0.47 MΩ

    TuningIndicator

  • Display pattern

    Converging dual fluorescent bars

    TuningIndicator

Characteristic

  • Grid bias end of control range

    -7 V

    TuningIndicator

Data set 04

1963 Philips Electron Tubes Handbook V1a

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Supply voltage

    250 V

    TriodeSection

  • Display/anode voltage

    250 V

    TriodeSection

  • Anode/display resistor

    470 kOhm

    TriodeSection

  • Grid resistor

    3 MOhm

    TriodeSection

  • Grid voltage

    0 V

    TriodeSection

  • Grid voltage

    -22 V

    TriodeSection

  • Plate-plus-display current

    0.45 mA

    GridVoltage=0V

  • Plate-plus-display current

    0.06 mA

    GridVoltage=-22V

SECTION 2

Tuning Indicator

Other

  • Indicator current

    1 mA

    GridVoltage=0V

  • Indicator current

    1.8 mA

    GridVoltage=-22V

  • Shadow length

    21 mm

    GridVoltage=0V

  • Shadow length

    0 mm

    GridVoltage=-22V

Data set 05

1967 Mullard Receiving Tubes for Maintenance

Published operating points and test conditions from this source.

SECTION 2

Tuning Indicator

Other

  • Ra

    470 kO

    TYPICAL OPERATIN G COND ITION S

  • Vg

    22 V

    TYPICAL OPERATIN G COND ITION S

  • Valh, max

    550 V

    TYPICAL OPERATIN G COND ITION S

  • Va max

    300 V

    TYPICAL OPERATIN G COND ITION S

  • Vg max. (Ig=

    1.3 V

    TYPICAL OPERATIN G COND ITION S

  • EM8

    4

    TYPICAL OPERATIN G COND ITION S

  • VOLTAGE INDICATOR EM8

    4

    TYPICAL OPERATIN G COND ITION S

  • Vg(V)

    0 V

    TYPICAL OPERATIN G COND ITION S

Data set 06

1968 Mazda Belvu

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Tension filament _ …mercermsererrencenseensenrensesaseencesessscennesunees VÊ

    6.3 V

  • Tension d'anode à courant nul .…..….…rrrevereesensesserrienreesss Va DI

    550 V

  • Tension d'anode ……s …… Va

    300 V

  • T'ension de l'électrode de commandeàcourant nu1 …… Vjbl

    550 V

  • Tension de l'électrode de COMmmANndE .. .………ecceneereseasseccss VI

    300 V

  • Tension de cible pour un courant d‘'anode nul ……s Vebl

    550 V

  • Tension de CIDIE ….……revcosecoseanseseanenceeneasusransencscenceseumencenceese VC

    300 V

  • Dissipation d'AnOdE ...s sressesseosssoascsssssusnenenssensecaess P

    0.5 W

  • Courant de cathode ….….….…….….….…. aorercécaseoureerencnsessesceonss 1K

    3 mA

  • Tension entre filament et cCathode@ .....….….….ssiesseecerercecse VIK

    100 V

  • Tension de grille pour un couränt de + 0,3 pA v VE

    1.3 V

Characteristic

  • Courant fIlAmeEnt L.…ousersesenentenenensenssensareseceocusnean ns ansec00e If

    210 mA

  • VN =

    250 V

  • le Ve =

    250 V

Data set 07

1972 Philips Receiving Tubes

Published operating points and test conditions from this source.

SECTION 2

Tuning Indicator

Characteristics

  • Heater voltage

    6.3 V

    Published nominal value

  • Heater current

    210 mA

    Published nominal value

Other

  • Maximum plate dissipation

    0.5 W

    Published or referenced maximum rating

  • Luminescent screen voltage

    250 V

    Published operating condition

  • Grid supply voltage range

    -22 to 0 V

    Published

Data set 08

1999 Philips E-Z

Published operating points and test conditions from this source.

SECTION 2

Tuning Indicator

Characteristic

  • Published electrical datum

    6.3 V

    Heater voltage Vi 6.3 V

  • Published electrical datum

    210 mA

    Heater current If 210 mA

  • Published electrical datum

    250 v

    Supply voltage Vp 250 v

  • Published electrical datum

    250 v

    Luminescent screen voltage Vg 250 v

  • Published electrical datum

    3 MQ

    Grid resistor Rg 3 MQ

  • Published electrical datum

    -22 V

    Grid supply voltage Vog 0 -22 V

  • Published electrical datum

    0.06 mA

    Amnode and deflection electrode current la+D 0.45 0.06 mA

  • Published electrical datum

    1.8 mA

    Luminescent screen current Ig -~ 1.0 1.8 mA

  • Published electrical datum

    -

    Shadow length a 2145 0 mm

  • Published electrical datum

    -

    Vog(V)—30 —20 -0 0

Other

  • Published electrical datum

    550 V

    Anode voltage Vao max. 550 V

  • Published electrical datum

    300 V

    Va max. 300 V

  • Published electrical datum

    0.5 W

    Anode dissipation Wy max. 0.5 W

  • Published electrical datum

    550 V

    Deflection electrode voltage VDo max. 550 V

  • Published electrical datum

    300 V

    Vp max. 300 V

  • Published electrical datum

    550 V

    Luminescent screen voltage Voo max. 550 V

  • Published electrical datum

    3 mA

    Cathode current Ix max. 3 mA

  • Published electrical datum

    3 MQ

    Grid resistor Rg max. 3 MQ

  • Published electrical datum

    100 V

    Cathode to heater voltage Vit max. 100 V

  • Heater voltage

    6.3 V

    Nominal heater rating

  • Heater current

    210 mA

    Nominal heater rating