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

Specialized - Photo Tube ·LightSource

CL61

Ferranti vacuum grid-controlled triode light source using blue phosphor, designed for high-speed stroboscopic photography and motion-analysis work.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
6.3 V / 300 mA

Description

The Ferranti CL61 is a vacuum grid-controlled triode light source for high-speed stroboscopic work, using a blue phosphor.

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
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

1 physical section, each with unique specifications.

Section 1

LightSource

X-ray radiationInterelectrode capacitances
Max plate voltage
20000 V
Max cathode current
0.2 mA

Grid-controlled electron-beam light-source triode.

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

1963 Ferranti

Published operating points and test conditions from this source.

SECTION 1

LightSource

Characteristics

  • Heater Voltage

    6.3 V

  • Heater Current

    300 mA

  • Grid Cutoff Voltage

    -30 V

    LowerMagnitudeLimit; range -30 to -80V

  • Grid Cutoff Voltage

    -80 V

    UpperMagnitudeLimit; range -30 to -80V

  • Maximum Grid Drive

    150 V

    ForMaximumAnodeCurrent

  • Phosphor Type

    P text

  • Fluorescence

    Blue text

  • Decay Time

    5 us

    Approximate

  • Light Output

    16000 cd

    Va=20kV; PeakBeamCurrent=100mA

Other

  • Maximum Anode Voltage

    20000 V

    NormalRating

  • Maximum Pulsed Anode Current

    100 mA

    Pulse

  • Maximum Mean Anode Current

    0.2 mA