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Specialized - Thyratron ·Thyratron

7240

Twenty-eight-volt-heater zero-bias miniature hydrogen thyratron for pulse generation and radar service. Fast discharge switching suits series-heater or vehicle equipment.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
B7G
Base pins
7
Nominal heater
28 V / 420 mA

Description

THE 7240 IS A ZERO BIAS MINIATURE HYDROGEN THYRATRON DESIGNED PRIMARILY

Socket description

Miniature 7-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B7G
Base pins
7
Nominal heater voltage
28 V
Nominal heater current
420 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

Thyratron

X-ray radiationInterelectrode capacitances
Max cathode current
20 A

Published ratings and characteristics promoted from approved datasheet.

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

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Thyratron

Characteristic

  • Gas

    Hydrogen

Other

  • PeakForwardAnodeVoltageMaximum

    1200 V

  • PeakInverseAnodeVoltageMaximum

    1200 V

  • Average Cathode Current Maximum

    50 mA

  • RMSCathodeCurrentMaximum

    1 A

  • OperatingFrequencyTested

    5000 Hz

  • CurrentRateOfRiseMaximum

    400 A/us

  • AnodeDelayTimeMaximum

    0.6 us

  • Cathode Heating Time

    30 s

  • ShockConditionMaximum

    720 g

    Duration=1ms

Data set 02

1966 Tung Sol Electronic Tubes 4 of 4

Published operating points and test conditions from this source.

SECTION 1

Thyratron

Other

  • Heater voltage

    28 V

    Nominal

  • Heater current

    420 mA

    Nominal

  • Maximum cathode current

    50 mA

    Promoted published value

  • HIGH PULSE REPETITION RATES. IN ADDITION ITS 28 VOLT HEATER MAKES IT

    28 mA

  • (WITH BOGIE HEATER VOLTAGE) If

    460 mA

  • DC ANODE VOLTAGE Ebb 3OO VOLTS

    3 V

    RATINGS

  • HEATER —CATHODE VOLTAGE Ehk —100 +Z

    5 V

    RATINGS

  • PEAK INVERSE GRID VOLTAGE egx

    150 V

    RATINGS

  • 11N PULSED OPERATION, THE PEAN INVERSE VOLTAGE, EXCLUSIVE OF A SPIKE OF 0.05 µGEC. MA%I MUM

    0.05 mA

    RATINGS

  • DURATION, SHALL NOT E%CERD

    25 V

    RATINGS

  • THE GRID VOLTAGE PULSE WHICH IS 2F PERCENT OF THE MA%I MUM UNLOADED PULSE AMPLITUDE AND THE

    2 mA

    RATINGS

  • TIME JITTER IS MEASURED AT

    50 A

    RATINGS

  • VOLTS AND ABOVE, JITTER NOT E%C EEDING

    0.005 V

    RATINGS

  • THE NOMINAL ALTITUDE RATINGFOR THE 7240 IS

    10000 ft

    RATINGS

  • HEATER POWER. THE BOGEY HEATER VOLTAGE OF

    28 V

    RATINGS

  • PEAK VOLTAGE

    500 V

    TYPICAL OPERATION

  • VOLTAGE RATE OF RISE PER µSEC. 35O VOLTS

    35 V

    TYPICAL OPERATION