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Voltage Radio Detector Converter ·Rectifier-Rectifier

8JU8A

Four-diode tube for color phase detection, noise-immune color-killer circuits, and FM stereo bridge matrixing. Its multiple diode elements serve signal detection and switching rather than high-current power rectification.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
9PQ
Socket code
B9A
Base pins
9
Nominal heater
8.4 V / 450 mA

Description

Quadruple-diode tube for color phase detection, noise-immune color-killer circuits, and FM stereo bridge matrixing.

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
9PQ
Socket code
B9A
Base pins
9
Nominal heater voltage
8.4 V
Nominal heater current
450 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

9PQ - Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

2 physical sections, each with unique specifications.

Section 1

Rectifier

X-ray radiationInterelectrode capacitances
Rectifier peak inverse voltage
300 V
Rectifier nominal output current
9 mA
Rectifier peak forward current
54 mA
Rectifier forward voltage drop
10 V

Inherited from explicit parent 6JU8A; supplied 8JU8A sheet changes heater characteristics only.

Section 2

Rectifier

X-ray radiationInterelectrode capacitances
Rectifier peak inverse voltage
300 V
Rectifier nominal output current
9 mA
Rectifier peak forward current
54 mA
Rectifier forward voltage drop
10 V

Second physical rectifier section; promoted electrical properties populated from identical section.

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

1971 RCA HB3 Binder 5 of 7

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Characteristic

  • Plate current at 70 V

    60 mA

    InstantaneousValue

Other

  • Maximum heater-cathode voltage, heater positive

    300 V

    EachUnit

  • Heater voltage nominal

    8.4 V

  • Heater current nominal

    450 mA

SECTION 2

Rectifier

Characteristic

  • Plate current at 70 V

    60 mA

    InstantaneousValue

Other

  • Maximum heater-cathode voltage, heater positive

    300 V

    EachUnit

Data set 02

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Peak Heater-Cathode Voltage

    300 V

    Other

  • Peak Inverse Plate Voltage

    300 V

    MaximumRating

  • Peak Plate Current

    54 mA

    MaximumRating

  • Average Output Current

    9 mA

    MaximumRating

  • Plate Current for plate voltage of

    10 V

    MaximumRating;PublishedValue1

  • Plate Current for plate voltage of

    60 V

    MaximumRating;PublishedValue2

  • Peak Inverse Plate Voltage

    300 V

    Section1

  • Nominal Output Current

    9 mA

    Section1

  • Peak Forward Current

    54 mA

    Section1

Capacitance

  • Unit No.l

    1.8 pF

    Capacitance

  • Unit No

    2 pF

    Capacitance;PublishedValue1

  • Unit No

    2.2 pF

    Capacitance;PublishedValue2

  • Plate of Unit No

    2 pF

    Capacitance;PublishedValue1

  • Plate of Unit No

    0.62 pF

    Capacitance;PublishedValue2

  • Unit No

    3 pF

    Capacitance;PublishedValue1

  • Unit No

    1.9 pF

    Capacitance;PublishedValue2

  • Unit No

    4 pF

    Capacitance;PublishedValue1

  • Unit No

    2.2 pF

    Capacitance;PublishedValue2

  • Plate of Unit No

    4 pF

    Capacitance;PublishedValue1

  • Plate of Unit No

    0.94 pF

    Capacitance;PublishedValue2

  • Cathode of Unit No.l to Heater and Internal Shield

    1.8 pF

    Capacitance

  • Cathode of Unit No

    3 pF

    Capacitance;PublishedValue1

  • Cathode of Unit No

    1.9 pF

    Capacitance;PublishedValue2

Characteristic

  • Forward Voltage Drop

    10 V

    Section1