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Specialized - Thyratron ·Thyratron

NL5720

Mercury-vapor thyratron with positive-grid characteristic, particularly useful where anode current must remain absent whenever no grid excitation is applied.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
DOWN
Socket code
-
Base pins
-
Nominal heater
5 V / 4.5 A

Description

NATIONAL POWER TUBE NL-5720/FG33 is a mercury vapor thyratron with a positive grid character- istic. It is especially useful in applications that require no current flow when there is no grid excitation. NL-5720/FG33 THYRATRON TUBE TECHNICAL INFORMATION do Amperes output (maximum) 2.5 Instantaneous amperes output (maximuin) 15 Maximum time of averaging anode current (seconds) 15 Maximum peak inverse volts 1000 Maximum peak forward volts 1000 Maxi

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
DOWN
Socket code
-
Base pins
-
Nominal heater voltage
5 V
Nominal heater current
4.5 A
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

DOWN - 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 plate voltage
1000 V
Max cathode current
2.5 A

Thyratron section; published switching/rating data retained below.

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

1956 National Electronics Industrial Tubes

Published operating points and test conditions from this source.

SECTION 1

Thyratron

Other

  • 2.5 Amperes do

    15 Amperes Peak A

    Source technical-information table; wording preserved from datasheet.

  • do Amperes output (maximum)

    2.5 A

    Source technical-information table; wording preserved from datasheet.

  • Instantaneous amperes output (maximuin)

    15 A

    Source technical-information table; wording preserved from datasheet.

  • Maximum time of averaging anode current (seconds)

    15 A

    Source technical-information table; wording preserved from datasheet.

  • Maximum peak inverse volts

    1000 V

    Source technical-information table; wording preserved from datasheet.

  • Maximum peak forward volts

    1000 V

    Source technical-information table; wording preserved from datasheet.

  • Maximum positive control-grid current average (one cycle averaging time) (amperes)

    250 mA

    Source technical-information table; wording preserved from datasheet.

  • Maximum negative control grid voltage Before conduction (volts)

    500 V

    Source technical-information table; wording preserved from datasheet.

  • During conduction (volts)

    10 V

    Source technical-information table; wording preserved from datasheet.

  • Maximum short circuit current (amperes)

    200 A

    Source technical-information table; wording preserved from datasheet.

  • Filament Volts

    5.0 | .25 V

    Source technical-information table; wording preserved from datasheet.

  • Filament currents (amps)

    4.5 ± .4 A

    Source technical-information table; wording preserved from datasheet.

  • Cathode heating time (seconds)

    300 s

    Source technical-information table; wording preserved from datasheet.

  • Critical grid current at Ep-220 V a-c (Maximum Microamperes)

    1000 A

    Source technical-information table; wording preserved from datasheet.

  • Anode drop at 8 amperes peak (volts)

    15 V

    Source technical-information table; wording preserved from datasheet.

  • Condensed mercury temperature limits (°C)

    +35 to +80 C

    Source technical-information table; wording preserved from datasheet.

  • No load (°C)

    26

    Source technical-information table; wording preserved from datasheet.

  • Full load (°C)

    37

    Source technical-information table; wording preserved from datasheet.

  • Net weight (ounces)

    5 oz

    Source technical-information table; wording preserved from datasheet.

  • Approx. shipping weight (lbs.)

    4 lb

    Source technical-information table; wording preserved from datasheet.

  • LIGHT FILAMENT BEFORE

    41PPLYING LOAD

    Source technical-information table; wording preserved from datasheet.

  • O

    2 | 4 | 6 | 8 | 10 | 12 | 14 | 16 | 18 | +20

    Source technical-information table; wording preserved from datasheet.

Characteristic

  • Anode to control grid capacitance (uuf)

    2.7 pF

    Source technical-information table; wording preserved from datasheet.

  • Control Grid to Cathode Capacitance (uuf)

    8 pF

    Source technical-information table; wording preserved from datasheet.

  • Ionization time (Approx. Microseconds)

    10 us

    Source technical-information table; wording preserved from datasheet.

  • Deionization time (Approx. Microseconds)

    1000 us

    Source technical-information table; wording preserved from datasheet.