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Voltage - Triode (with diode, heptode or hexode) ·Diode-Diode-Triode

55

Early double-diode low-mu triode for detector, AVC, and audio amplifier service. The diode elements provide signal and control-voltage rectification while the relatively low-resistance triode supplies useful current drive after detection.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
3
Base
-
Socket code
UX6
Base pins
6
Nominal heater
2.5 V / 1 A

Description

Double-diode triode for detector and amplifier service.

Socket description

Small 6-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
UX6
Base pins
6
Nominal heater voltage
2.5 V
Nominal heater current
1 A
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 plate voltage
250 V
Max cathode current
1 mA

Representative row for two identical diode sections sharing the cathode with the triode.

Section 2

Diode

X-ray radiationInterelectrode capacitances
Max plate voltage
250 V
Max cathode current
1 mA

Second physical diode section; identical detector diode added to align physical rows with SectionCount.

Section 3

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
7500 Ω
Transconductance
0.0011 S
Amplification factor
8.3
Max plate voltage
250 V
Max plate dissipation
2 W
Max cathode current
10 mA

Triode section; 250-V operating column used for promoted characteristics.

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

1937 Raytheon Radio Receiving Tubes

Published operating points and test conditions from this source.

SECTION 1

Diode

Other

  • Number of identical diode units

    2 count

    IdenticalSectionsCompressed

SECTION 3

Triode

Capacitance

  • Grid-to-plate capacitance

    1.7 pF

    TriodeSection

  • Input capacitance

    2 pF

    TriodeSection

  • Output capacitance

    3.5 pF

    TriodeSection

Other

  • Plate voltage

    135 V

    ClassA

  • Grid bias

    -10.5 V

    ClassA; PlateVoltage=135V

  • Plate current

    3.7 mA

    ClassA; PlateVoltage=135V

  • Power output

    75 mW

    ClassA; PlateVoltage=135V

  • Plate voltage

    180 V

    ClassA

  • Grid bias

    -13.5 V

    ClassA; PlateVoltage=180V

  • Plate current

    6 mA

    ClassA; PlateVoltage=180V

  • Power output

    160 mW

    ClassA; PlateVoltage=180V

  • Plate voltage

    250 V

    ClassA

  • Grid bias

    -20 V

    ClassA; PlateVoltage=250V

  • Plate current

    8 mA

    ClassA; PlateVoltage=250V

  • Power output

    300 mW

    ClassA; PlateVoltage=250V

Characteristic

  • Plate resistance

    11000 ohm

    ClassA; PlateVoltage=135V

  • Transconductance

    760 uS

    ClassA; PlateVoltage=135V

  • Plate resistance

    8500 ohm

    ClassA; PlateVoltage=180V

  • Transconductance

    975 uS

    ClassA; PlateVoltage=180V

  • Plate resistance

    7500 ohm

    ClassA; PlateVoltage=250V

  • Transconductance

    1100 uS

    ClassA; PlateVoltage=250V

Data set 02

1940 RCA

Published operating points and test conditions from this source.

SECTION 1

Diode

Other

  • HeaterVoltageNominal

    2.5 V

    Nominal

  • HeaterCurrentNominal

    1 A

    Nominal

  • Maximum Plate Voltage

    250 V

  • Maximum Cathode Current

    1 mA

SECTION 3

Triode

Other

  • HeaterVoltageNominal

    2.5 V

    Nominal

  • HeaterCurrentNominal

    1 A

    Nominal

  • Maximum Plate Voltage

    250 V

  • Maximum Cathode Current

    10 mA

Characteristic

  • Transconductance

    1040 µS

    Typical

  • Amplification Factor

    8.3

    Typical

  • Plate Resistance

    8000 ohm

    Typical

Data set 03

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Diode

Other

  • Heater voltage

    2.5 V

    Nominal

  • Heater current

    1 A

    Nominal

Characteristic

  • Plate current

    3.7 mA

    Published operating table; OperatingPoint1

  • Plate current

    6 mA

    Published operating table; OperatingPoint2

  • Plate current

    8 mA

    Published operating table; OperatingPoint3

  • Transconductance

    750 uS

    Published operating table; OperatingPoint1

  • Transconductance

    975 uS

    Published operating table; OperatingPoint2

  • Transconductance

    1100 uS

    Published operating table; OperatingPoint3

  • Plate resistance

    11000 ohm

    Published operating table; OperatingPoint1

  • Plate resistance

    8500 ohm

    Published operating table; OperatingPoint2

  • Plate resistance

    7500 ohm

    Published operating table; OperatingPoint3

SECTION 3

Triode

Other

  • Heater voltage

    2.5 V

    Nominal

  • Heater current

    1 A

    Nominal

Characteristic

  • Plate current

    3.7 mA

    Published operating table; OperatingPoint1

  • Plate current

    6 mA

    Published operating table; OperatingPoint2

  • Plate current

    8 mA

    Published operating table; OperatingPoint3

  • Transconductance

    750 uS

    Published operating table; OperatingPoint1

  • Transconductance

    975 uS

    Published operating table; OperatingPoint2

  • Transconductance

    1100 uS

    Published operating table; OperatingPoint3

  • Plate resistance

    11000 ohm

    Published operating table; OperatingPoint1

  • Plate resistance

    8500 ohm

    Published operating table; OperatingPoint2

  • Plate resistance

    7500 ohm

    Published operating table; OperatingPoint3