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Tuning Indicator ·Triode-Triode-TuningIndicator

EMM801

Voltage-comparison indicator combining two matched triode control systems with a fluorescent shadow display for balancing, monitoring, and null-indication applications.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
3
Base
-
Socket code
B9A
Base pins
9
Nominal heater
6.3 V / 300 mA

Description

Voltage-comparison indicator tube combining two triode control systems with a visual shadow display.

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
-
Socket code
B9A
Base pins
9
Nominal heater voltage
6.3 V
Nominal heater current
300 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

3 physical sections, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
19000 Ω
Transconductance
0.001 S
Amplification factor
19
Max plate voltage
300 V
Max plate dissipation
0.2 W
Max cathode current
12 mA

Triode section; maximum ratings are published per system.

Section 2

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
19000 Ω
Transconductance
0.001 S
Amplification factor
19
Max plate voltage
300 V
Max plate dissipation
0.2 W
Max cathode current
12 mA

Triode section; maximum ratings are published per system.

Section 3

Tuning Indicator

X-ray radiationInterelectrode capacitances
Max plate voltage
300 V
Max cathode current
12 mA

Visual indicator section; specialized indicator values preserved as parameters.

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 AEG

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Plate voltage

    100 V

  • Control-grid voltage

    -2 V

  • Plate current

    2.8 mA

  • Transconductance

    1000 uS

  • Amplification factor

    19

Other

  • No-load plate voltage

    - to 550 V

  • Heater-cathode voltage

    - to 100 V

SECTION 2

Triode

Characteristic

  • Plate voltage

    100 V

  • Control-grid voltage

    -2 V

  • Plate current

    2.8 mA

  • Transconductance

    1000 uS

  • Amplification factor

    19

Other

  • No-load plate voltage

    - to 550 V

  • Heater-cathode voltage

    - to 100 V

SECTION 3

Tuning Indicator

Other

  • Supply voltage

    200 V

  • Supply voltage

    250 V

  • Indicator load resistance

    400 kOhm

  • Maximum shadow-length difference

    2 mm

Data set 02

1959 Telefunken

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Triode plate voltage

    100 V

    EachTriode

  • Triode control-grid voltage

    -2 V

    EachTriode

  • Triode plate current

    2.8 mA

    EachTriode

  • Triode transconductance

    1000 uS

    EachTriode

  • Triode amplification factor

    19 ratio

    EachTriode

Other

  • Display supply voltage

    200 V

  • Display supply voltage

    250 V

  • Anode series resistance

    400 kOhm

    EachTriode

  • Display current

    1.4 mA

    Ub=200V

  • Display current

    1.8 mA

    Ub=250V

  • Display cold voltage

    550 V

  • Display voltage maximum

    300 V