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Specialized - Switching Tube ·Thyratron

Z804U

Cold-cathode negative-trigger tube for relay and switching operation from AC or DC supplies. Heaterless gas discharge provides abrupt electronic control.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
B9A
Base pins
-
Nominal heater
-

Description

The Z804U is a cold-cathode trigger tube intended primarily for relay and switching service. It is negatively triggered and can operate directly from mains-frequency AC supplies or from DC supplies within its published limits.

Socket description

Small-button Noval 9-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B9A
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

Thyratron

X-ray radiationInterelectrode capacitances
Max plate voltage
350 V
Max cathode current
25 mA
Regulator minimum current
5 mA
Regulator maximum current
40 mA
Regulator starting voltage
131 V
Regulator maintaining voltage
110.5 V

Gas-filled cold-cathode relay tube with negative starter voltage.

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

1957 Philips Receiving and Amplifying Tubes

Published operating points and test conditions from this source.

SECTION 1

Thyratron

Characteristic

  • StarterIgnitionVoltageMinimum

    -131 V

    AnodeVoltage=180-350V

  • StarterIgnitionVoltageMaximum

    -115 V

    AnodeVoltage=180-350V

  • MaintainingVoltageMinimum

    106 V

    AnodeCurrent=20mA

  • MaintainingVoltageMaximum

    115 V

    AnodeCurrent=20mA

Data set 02

1963 Amperex Condensed

Published operating points and test conditions from this source.

SECTION 1

Thyratron

Other

  • Anode voltage range

    180 to 350 V

    DC

  • Peak cathode current

    125 mA

  • Cathode current range

    5 to 40 mA

    DC

  • Anode voltage range AC

    180 to 275 V

    AC

  • Cathode current range AC

    5 to 25 mA

    AC

Characteristic

  • Starter-to-cathode breakdown voltage

    -131 to -115 V

  • Anode-to-cathode sustaining voltage

    106 to 115 V

  • Anode-to-cathode breakdown voltage

    >400 V

Data set 03

1963 Mullard

Published operating points and test conditions from this source.

SECTION 1

Thyratron

Characteristics

  • Trigger ignition voltage range

    -115 to -131 V

    NegativeTrigger

  • Anode maintaining voltage range at 20 mA

    106 to 115 V

  • Transfer current typical at 210 V

    10 uA

  • Trigger ignition voltage variation over life maximum

    5 V

  • Anode maintaining voltage variation over life maximum

    3 V

  • Trigger potential after ignition approximate

    20 V

  • Trigger ignition hysteresis typical

    3 V

Other

  • Positive trigger current maximum

    400 uA

  • Negative trigger current maximum

    400 uA

  • AC mains voltage maximum RMS

    275 V

    AC

  • AC mains voltage minimum RMS

    180 V

    AC

  • AC supply frequency maximum

    100 Hz

    AC

  • AC supply frequency minimum

    10 Hz

    AC

  • Mean anode current maximum

    25 mA

    AC

  • Mean anode current minimum

    5 mA

    AC

  • Peak anode current maximum

    125 mA

    AC,Pulse

  • DC supply voltage maximum

    350 V

    DC

  • DC supply voltage minimum

    210 V

    DC

  • DC anode current maximum

    40 mA

    DC

  • DC anode current minimum

    5 mA

    DC

  • Trigger ignition voltage typical

    -120 V

    NegativeTrigger

  • Cathode connection resistor

    2 Mohm

Application

  • Application

    Relay / switching control

Data set 04

1963 Philips Electron Tubes Handbook V2

Published operating points and test conditions from this source.

SECTION 1

Thyratron

Characteristic

  • Starter breakdown voltage

    -131 to -115 V

    AnodeSupply=180-350V DC

  • Anode maintaining voltage at 20 mA

    106 to 115 V

  • Starter maintaining voltage at 100 uA

    100 V

  • Starter breakdown drift

    - to 5 V

    Maximum

Other

  • Nominal AC mains voltage minimum

    200 to - V RMS

  • Minimum cathode current

    5 to - mA

  • Maximum cathode current

    - to 40 mA

Data set 05

1999 Philips E-Z

Published operating points and test conditions from this source.

SECTION 1

Thyratron

Other

  • Starter ignition voltage

    -123 V

  • Maintaining voltage

    110 V

    Ik=20mA

  • Anode ignition voltage

    400 V