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Voltage Regulator ·VoltageRegulator

85A1

Neon-filled precision reference tube maintaining approximately 85 V over about 1–8 mA, emphasizing stable reference performance rather than high-current regulation.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
Loctal
Socket code
B8G
Base pins
8
Nominal heater
-

Description

The Mullard 85A1 is a neon-filled two-electrode reference tube designed for very stable maintaining voltage.

Socket description

Loctal 8-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
Loctal
Socket code
B8G
Base pins
8
Nominal heater voltage
-
Nominal heater current
-
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

Loctal - 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

Voltage Regulator

X-ray radiationInterelectrode capacitances
Regulator voltage
85 V
Regulator minimum current
1 mA
Regulator maximum current
8 mA
Regulator starting voltage
125 V
Regulator maintaining voltage
85 V
Regulator dynamic impedance
290 Ω

Cold-cathode gas-filled Philips voltage stabilizer/reference tube.

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

1951 Mullard Valve and Service Manual

Published operating points and test conditions from this source.

SECTION 1

Voltage Regulator

Other

  • Preferred Quiescent Current

    4.5 mA

    ±0.2mA

Characteristics

  • Burning Voltage Minimum

    83 V

  • Burning Voltage Maximum

    86 V

  • Temperature Coefficient

    -1.8 mV/degF

Data set 02

1953 Amperex

Published operating points and test conditions from this source.

SECTION 1

Voltage Regulator

Characteristics

  • Operating voltage

    83 to 87 V

  • Operating current

    1 to 8 mA

Data set 03

1957 Philips Receiving and Amplifying Tubes

Published operating points and test conditions from this source.

SECTION 1

Voltage Regulator

Characteristics

  • Maintaining/Reference Voltage

    85 V

Other

  • Minimum Current

    1 mA

  • Maximum Current

    8 mA

  • Ignition Voltage Maximum

    125 V

Data set 04

1963 Mullard

Published operating points and test conditions from this source.

SECTION 1

Voltage Regulator

Other

  • Minimum Ignition Voltage

    125 V

  • Maximum Burning Current

    8 mA

  • Minimum Burning Current

    1 mA

  • Preferred Burning Current

    4.5 mA

    Approximate

  • Maximum Negative Anode Voltage

    75 V

Characteristics

  • Maintaining Voltage Minimum

    83 V

    AtPreferredCurrent

  • Maintaining Voltage Maximum

    86 V

    AtPreferredCurrent

  • Incremental Resistance Average

    290 ohm

  • Incremental Resistance Maximum

    450 ohm

Data set 05

1963 Philips Electron Tubes Handbook V2

Published operating points and test conditions from this source.

SECTION 1

Voltage Regulator

Characteristic

  • Maintaining voltage at 4 mA

    83 to 87 V

  • Voltage regulation

    - to 4 V

    Ia=1-8mA

  • Temperature coefficient

    -3.2 mV/degC

Data set 06

1999 Philips 0-D

Published operating points and test conditions from this source.

SECTION 1

Voltage Regulator

Characteristics

  • Maintaining voltage range

    81 to 87 V

    Published datasheet value

  • Maximum dynamic resistance

    - to 430 Ω

    Published datasheet value

  • Maximum regulation

    - to 4 V

    1–8 mA

  • Temperature coefficient

    -3.2 mV/°C

    Published datasheet value

Other

  • Recommended quiescent current

    4 mA

    Published datasheet value