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Tuning Indicator ·Triode-TuningIndicator

UM11

Series-heater luminous tuning indicator with two shadow sectors of differing sensitivity, providing useful indication for both weak and strong received signals.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
-
Socket code
Y8A
Base pins
-
Nominal heater
15 V / 100 mA

Description

The UM11 is a luminous tuning indicator for series-heater receivers. Two separate shadow sectors provide a sensitive indication range for weak stations and a broader range for strong stations.

Socket description

Steel-tube 8-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
Y8A
Base pins
-
Nominal heater voltage
15 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

Triode

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

Sensitive indicator range.

Section 2

Tuning Indicator

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

Strong-signal indicator range.

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 RFT Rundfunk Technik

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Target Voltage

    200 V

SECTION 2

Tuning Indicator

Other

  • Indicator screen voltage

    200 V

    StrongSignalRange

Characteristic

  • Grid-control range

    0 to -20 V

    StrongSignalRange

Data set 02

1959 Telefunken

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Luminous-screen voltage

    200 V

  • Luminous-screen current

    0.4 mA

    GridVoltage=0V

  • Maximum luminous-screen voltage

    250 V

  • Minimum luminous-screen voltage

    90 V

Characteristics

  • Grid voltage sensitive range

    0 to -3 V

    ShadowPair1

  • Grid voltage strong-signal range

    0 to -20 V

    ShadowPair2