Skip to main content
Tube Tinker — Electron Tube Database
Alternatives & variationsDownload PDF datasheet

Tuning Indicator ·Pentode-TuningIndicator

UFM11

Series-heater luminous-screen indicator combining variable-pentode action with a fluorescent shadow display whose angle changes with control voltage.

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

Description

The UFM11 combines a variable pentode action with a luminous screen whose shadow angle changes with control voltage. The datasheet supplies operating points for 100 V and 200 V systems and limits for the luminous screen.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
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

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
600000 Ω
Max plate voltage
300 V
Max screen voltage
300 V
Max plate dissipation
0.4 W
Max screen dissipation
0.2 W
Max cathode current
4 A

Indicator/pentode section with luminous screen; source gives shadow angle versus control voltage.

Section 2

Tuning Indicator

X-ray radiationInterelectrode capacitances

No fixed ratings are recorded for this section.

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

1959 Telefunken

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Supply and luminous-screen voltage

    200 V

  • Plate voltage

    69 V

  • Screen voltage

    14 V

  • Luminous-screen current

    1.05 mA

  • Maximum luminous-screen voltage

    275 V

  • Minimum luminous-screen voltage

    90 V

Capacitance

  • Heater-to-grid capacitance

    0.05 pF