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Voltage Radio Detector Converter ·Diode-Diode-Pentode

UBF89

Series-heater double-diode variable-mu pentode for high-gain RF/IF amplification, AM detection, and automatic volume control. Paired diodes provide detector and AVC rectification.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
3
Base
-
Socket code
B9A
Base pins
9
Nominal heater
19 V / 100 mA

Description

Double-diode variable-mu pentode for detection and intermediate-frequency amplification. The supplied French datasheet was translated to English for descriptive output.

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
9
Nominal heater voltage
19 V
Nominal heater current
100 mA
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

3 physical sections, each with unique specifications.

Section 1

Diode

X-ray radiationInterelectrode capacitances
Max cathode current
0.8 mA
Rectifier peak inverse voltage
200 V
Rectifier nominal output current
0.8 mA
Rectifier peak forward current
5 mA

Representative section for two diode systems sharing the common cathode.

Section 2

Diode

X-ray radiationInterelectrode capacitances

No fixed ratings are recorded for this section.

Second physical detector diode section added in approved reconciliation.

Section 3

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
600000 Ω
Transconductance
0.005 S
Amplification factor
20
Max plate voltage
200 V
Max screen voltage
300 V
Max plate dissipation
2.25 W
Max screen dissipation
0.45 W
Max cathode current
16.5 mA

Published ratings and characteristics promoted from the approved source.

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 3

Pentode

Characteristics

  • Cutoff characteristic

    Variable-mu

Application

  • Application

    RF / IF amplifier

Data set 02

195X Tesla

Published operating points and test conditions from this source.

SECTION 3

Pentode

Characteristic

  • Plate Current

    12 mA

    Plate 170 V

Data set 03

1961 Ferranti Technical Handbook

Published operating points and test conditions from this source.

SECTION 1

Diode

Application

  • Application

    AM detector / AVC

SECTION 3

Pentode

Characteristics

  • Cutoff characteristic

    Variable-mu

Application

  • Application

    RF / IF / AF amplifier

Data set 04

1963 Philips Electron Tubes Handbook V1

Published operating points and test conditions from this source.

SECTION 1

Diode

Other

  • Maximum inverse voltage

    350 V

  • Maximum average diode current

    0.8 mA

  • Maximum peak diode current

    5 mA

SECTION 3

Pentode

Other

  • Plate voltage

    170 V

    RF/IF amplifier

  • Screen voltage

    100 V

    RF/IF amplifier

  • Plate current

    12 mA

    RF/IF amplifier

  • Screen current

    3.3 mA

    RF/IF amplifier

  • Maximum plate voltage

    250 V

  • Maximum screen voltage

    250 V

  • Maximum plate dissipation

    2 W

Characteristic

  • Transconductance

    5000 uS

    RF/IF amplifier

  • Plate resistance

    0.4 Mohm

    RF/IF amplifier

Data set 05

1972 Philips Receiving Tubes

Published operating points and test conditions from this source.

SECTION 1

Diode

Other

  • HeaterVoltageNominal

    19 V

    Nominal

  • HeaterCurrentNominal

    100 mA

    Nominal

  • Maximum Cathode Current

    0.8 mA

  • Maximum Peak Inverse Voltage

    200 V

  • Rectified Output Current

    0.8 mA

  • PeakForwardCurrent

    5 mA

SECTION 3

Pentode

Other

  • HeaterVoltageNominal

    19 V

    Nominal

  • HeaterCurrentNominal

    100 mA

    Nominal

  • Maximum Plate Voltage

    250 V

  • Maximum Screen Voltage

    250 V

  • Maximum Plate Dissipation

    2.25 W

  • Maximum Screen Dissipation

    0.45 W

  • Maximum Cathode Current

    16.5 mA

Characteristic

  • Transconductance

    4500 µS

    Typical

  • Amplification Factor

    20

    Typical

  • Plate Resistance

    600000 ohm

    Typical

Data set 06

1973 Mazda Valves Binder 2

Published operating points and test conditions from this source.

SECTION 1

Diode

Characteristics

  • Heater or filament voltage

    19 V

    Published nominal value

  • Heater or filament current

    100 mA

    Published nominal value

SECTION 3

Pentode

Characteristics

  • Heater or filament voltage

    19 V

    Published nominal value

  • Heater or filament current

    100 mA

    Published nominal value

  • Transconductance

    4500 µS

    Published operating characteristic

Other

  • Maximum plate dissipation

    2.25 W

    Published maximum rating

Data set 07

1999 Philips E-Z

Published operating points and test conditions from this source.

SECTION 3

Pentode

Other

  • Typical anode current

    11 mA

    Pentode

Characteristic

  • Transconductance

    4500 µS

    Pentode

  • Amplification factor g2-g1

    20

    Pentode