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Specialized - Photo Tube ·LightSource

CL55

Compact heated spectral light source filled with spectrally pure helium for laboratory wavelength-reference applications.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
6.3 V / 1.5 A

Description

The Ferranti CL55 is a compact heated spectral light source filled with spectrally pure helium gas.

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
1.5 A
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

No fixed ratings are recorded for this section.

Heated spectral gas-discharge light-source 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

1963 Ferranti

Published operating points and test conditions from this source.

SECTION 1

LightSource

Characteristics

  • Heater Voltage

    6.3 V

  • Heater Current

    1.5 A

  • Gas Filling

    Helium text

  • Minimum Supply Voltage

    500 V

  • Anode-Cathode Voltage Drop

    95 V

    Approximate

  • Minimum Cathode Heating Delay

    60 s

    BeforeHT

Other

  • Maximum Mean Anode Current

    40 mA

  • Maximum Peak Cathode Current

    90 mA

  • Trigger Electrode Resistor

    22000 ohm

    TriggerToAnode