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Specialized - Traveling Wave ·TravelingWave

CMA1257

Compact liquid-cooled M-type Carcinotron covering 7.2–8.7 GHz, electronically tunable with integral permanent-magnet focusing and at least 160 watts RF output.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
6.3 V / 2.25 A

Description

The Thomson-CSF CMA1257 is a rugged, compact M-type Carcinotron: an electronically tunable cross-field backward-wave oscillator with integral permanent-magnet focusing, liquid cooling, and at least 160 W output over 7.20–8.70 GHz.

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
2.25 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

TravelingWave

X-ray radiationInterelectrode capacitances
Max cathode current
300 mA

Crossed-field backward-wave oscillator section. Fixed schema has no line/sole/beam-voltage promoted fields; line current is stored in MaxCathodeCurrent as the published electron-stream current, with complete specialized values in parameters.

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

1972 Thomson CSF

Published operating points and test conditions from this source.

SECTION 1

TravelingWave

Characteristic

  • Heater voltage nominal

    6.3 V

  • Heater current

    1.5 A to 3 A

  • Frequency range

    7.2 to 8.7 GHz

Other

  • Minimum RF output power

    160 W

    Frequency=7.2-8.7GHz

  • Warm-up time minimum

    3 min

  • Typical heater current

    1.7 A

  • Typical sole voltage

    -1.2 kV

  • Typical anode voltage, low-frequency end

    1.36 kV

  • Typical anode voltage, high-frequency end

    1.34 kV

  • Typical line voltage, low-frequency end

    2.7 kV

  • Typical line voltage, high-frequency end

    4.26 kV

  • Typical line current

    300 mA

  • Typical RF output power, low-frequency end

    205 W

  • Typical RF output power, high-frequency end

    235 W

  • Heater voltage limit minimum

    6 V

  • Heater voltage limit maximum

    6.6 V

Capacitance

  • Sole-to-all-other-electrodes capacitance maximum

    35 pF

  • Anode-to-all-other-electrodes capacitance maximum

    10 pF

  • Line-to-all-other-electrodes capacitance maximum

    35 pF