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Specialized - Cathode Ray ·CathodeRay

7QR20

Small Tesla cathode-ray display tube for compact oscillographs and continuous monitoring of complex electrical waveforms, using electrostatic focusing and asymmetric electrostatic deflection at approximately 1 kV.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
-
Base pins
8
Nominal heater
6.3 V / 700 mA

Description

TESLA 7QR20 is a small cathode-ray display tube for compact oscillographs or continuous monitoring of complex electrical waveforms, with electrostatic focusing and asymmetric electrostatic deflection.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
8
Nominal heater voltage
6.3 V
Nominal heater current
700 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

Cathode Ray

X-ray radiationInterelectrode capacitances
Max plate voltage
1000 V

Electrical section mapped from published characteristics and maximum ratings.

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

195X Tesla

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Characteristic

  • Useful screen diameter

    60 mm

  • Deflection sensitivity D1-D2 at 500 V

    0.44 mm/V

  • Deflection sensitivity D1-D2 at 800 V

    0.275 mm/V

Other

  • Plate voltage

    500 V

  • Plate voltage

    800 V