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Specialized - Klystron ·Klystron

SY31

Rugged low-noise water-cooled two-resonator klystron amplifier centered near 9.5 GHz, providing approximately 175–200 W continuous X-band output.

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

Description

Ferranti SY31 is a rugged, low-noise, water-cooled two-resonator klystron power amplifier for CW X-band operation. It is centered near 9.5 GHz, with typical 175-200 W output at about 8 kV and 150 mA.

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

Klystron

X-ray radiationInterelectrode capacitances
Max plate voltage
10000 V
Max cathode current
260 mA

Klystron beam/resonator anode voltage is promoted to MaxPlateVoltage where applicable; original published labels and conditions are retained in parameter rows.

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

Klystron

Other

  • Heater power

    20 to 27 W

    Published range

  • Heater resistance at 23.5 W

    2.35 to 2.65 ohm

  • Cold heater resistance

    0.2 ohm

  • Maximum heater switching surge

    9 A

  • Maximum beam voltage

    10 kV

  • Maximum beam current

    260 mA

  • Maximum focus voltage

    50 V

  • Typical beam voltage

    8 kV

  • Typical beam current

    150 mA

  • Typical focus voltage

    -25 V

  • Typical efficiency

    17 %

  • Typical input power

    15 to 25 W

  • Typical output power

    175 to 200 W

  • Maximum output VSWR

    2

    Recommended limit

Frequency

  • Operating frequency

    9500 Mc/s

    Nominal

  • Tuning range

    20 Mc/s

    ±20 Mc/s

Cooling

  • Minimum water flow

    1 L/min

    At 20 C

Characteristic

  • Typical high-level RF gain

    10 dB

  • Typical low-level RF gain

    14 dB