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Specialized - Photo Tube ·PhotoemissiveDetector

FZ21G

Blue-sensitive photoelectric cell with inert-gas filling and a caesium-antimony photocathode. Gas enhancement increases photocurrent for direct measurement of blue and visible optical radiation.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
-

Description

Blue-sensitive photoelectric cell with inert-gas filling and caesium-antimony cathode.

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
-
Nominal heater current
-
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

PhotoemissiveDetector

X-ray radiationInterelectrode capacitances
Max cathode current
0.005 mA

Photocell section; maximum average photocathode current promoted to MaxCathodeCurrent.

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 AEG

Published operating points and test conditions from this source.

SECTION 1

PhotoemissiveDetector

Other

  • Operating voltage maximum

    90 V

    Intermittent short-on operation

  • Cathode current crest maximum

    15 uA

    Entire cathode surface illuminated

  • Cathode current average maximum

    5 uA

    Entire cathode surface illuminated

  • Cathode surface area

    6.5 cm2

  • Ambient temperature maximum

    50 degC

Capacitance

  • Cell capacitance

    1.5 pF

Characteristic

  • Spectral sensitivity maximum wavelength

    400 nm