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Nixie ·Nixie

SZ31

Cold-cathode numerical indicator tube for visual display and counting applications; despite appearing in this klystron batch, it is a Nixie-type indicator rather than a microwave tube.

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

Description

SZ31 is a cold-cathode numerical indicator, classified as Nixie for this batch. The supplied datasheet was reviewed for operating conditions, ratings, and display/counting characteristics.

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

Nixie

X-ray radiationInterelectrode capacitances
Max plate voltage
8000 V
Max cathode current
40 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

Nixie

Other

  • Heater voltage

    7 to 8.5 V

  • Heater input power

    15.5 to 21 W

  • Heater resistance at 18 W

    1.9 to 2.1 ohm

  • Cold heater resistance

    0.2 ohm

  • Maximum heater switching surge

    8 A

  • Maximum beam voltage

    8 kV

  • Maximum beam current

    40 mA

  • Typical beam voltage

    6.8 to 7.4 kV

  • Typical beam current

    28 to 30 mA

  • Output power

    10 to 20 W

Frequency

  • Operating frequency

    8000 to 9000 Mc/s

  • Tuning range

    20 Mc/s

    ±20 Mc/s

Cooling

  • Water flow

    0.3 to 3 L/min

    Published min/max

Characteristic

  • Frequency pushing with beam voltage

    3 kc/s/V

  • Frequency pushing with heater current

    200 c/s/A

  • Frequency pulling

    4.5 Mc/s

  • Temperature coefficient

    150 kc/s/C

Data set 02

196X Nixie Random Datasheets

Published operating points and test conditions from this source.

SECTION 1

Nixie

Other

  • Supply Voltage

    170 V

    Published datasheet value

  • Maximum/Normal Cathode Current

    3 mA

    Published datasheet value

Characteristic

  • Ignition/Starting Voltage

    170 V

    Published datasheet value

  • Minimum Cathode/Anode Current

    2 mA

    Published datasheet value