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Tuning Indicator ·Triode-TuningIndicator

UM34

Electron-beam fluorescent tuning indicator using a 12.6 V heater and otherwise electrically equivalent to EM34, providing visual receiver tuning response.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
-
Socket code
IO
Base pins
-
Nominal heater
12.6 V / 100 mA

Description

The Mullard UM34 is an electron-beam tuning indicator using a 12.6 V, 0.1 A heater; it is otherwise identical to the EM34.

Socket description

International Octal

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
IO
Base pins
-
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

2 physical sections, each with unique specifications.

Section 1

Tuning Indicator

X-ray radiationInterelectrode capacitances
Max plate voltage
250 V

Tuning indicator with two display systems of different sensitivity for 100 mA series-heater service.

Section 2

Triode

X-ray radiationInterelectrode capacitances
Max plate voltage
250 V

Tuning indicator with two display systems of different sensitivity for 100 mA series-heater service.

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

1951 Mullard Valve and Service Manual

Published operating points and test conditions from this source.

SECTION 2

Triode

Other

  • Target Voltage

    200 V

  • Target Current

    0.55 mA

  • Control Voltage for Maximum Shadow Angle

    0 V

  • Control Voltage for Minimum Shadow Angle

    -4.2 V

    Deflector plate set 1

  • Control Voltage for Minimum Shadow Angle

    -12.5 V

    Deflector plate set 2

  • Maximum Target Voltage

    550 V

  • Maximum Electrode Voltage

    275 V

  • Maximum Heater-Cathode Voltage

    100 V

Data set 02

1957 Philips Receiving and Amplifying Tubes

Published operating points and test conditions from this source.

SECTION 1

Tuning Indicator

Characteristic

  • Heater Voltage

    12.6 V

  • Heater Current

    100 mA

  • DisplaySystems

    2

    DifferentSensitivity

Data set 03

1963 Philips Electron Tubes Handbook V1

Published operating points and test conditions from this source.

SECTION 1

Tuning Indicator

Other

  • Supply voltage

    100 V

    Indicator

  • Series resistor

    1 MOhm

    Indicator

  • Anode current at grid 0 V

    0.4 mA

    Indicator

  • Grid voltage for minimum shadow

    -2.5 V

    System1

  • Supply voltage

    200 V

    Indicator

  • Anode current at grid 0 V

    1.4 mA

    Indicator

  • Grid voltage for minimum shadow

    -4.2 V

    System1

SECTION 2

Triode

Other

  • Grid voltage for minimum shadow

    -8 V

    System2; SupplyVoltage=100V

  • Grid voltage for minimum shadow

    -12.5 V

    System2; SupplyVoltage=200V