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Tube Tinker — Electron Tube Database
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Diode (NOT rectifier) ·Diode

R290

Directly heated diode noise-source tube designed for electronic noise measurements, with a normal-support resonance near 1.425 GHz.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
1.85 V / 2.7 A

Description

Directly heated diode noise-source tube for noise measurements, with a normal-support resonance near 1425 MHz.

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
1.85 V
Nominal heater current
2.7 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

Diode

X-ray radiationInterelectrode capacitances
Max plate voltage
100 V
Max plate dissipation
3 W

Published ratings and characteristics promoted from the approved source.

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 La Radiotechnique

Published operating points and test conditions from this source.

SECTION 1

Diode

Other

  • HeaterVoltageNominal

    1.85 V

    Nominal

  • HeaterCurrentNominal

    2.7 A

    Nominal

  • Maximum Plate Voltage

    100 V

  • Maximum Plate Dissipation

    3 W

Characteristic

  • ResonanceFrequency

    1425 MHz

    Tube on normal support