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Voltage - Triode (single) ·Triode

56

General-purpose triode for detector and amplifier service in receiving and general electronic equipment.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
5A
Socket code
UX5
Base pins
5
Nominal heater
2.5 V / 1 A

Description

General-purpose detector and amplifier triode.

Socket description

Small 5-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
5A
Socket code
UX5
Base pins
5
Nominal heater voltage
2.5 V
Nominal heater current
1 A
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

5A - 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

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
9500 Ω
Transconductance
0.00146 S
Amplification factor
13.8
Max plate voltage
250 V
Max cathode current
10 mA

Source states ratings are identical to type 76 but does not reproduce the maximum-rating table; only directly printed operating characteristics are promoted (reference/equivalence sparse exception).

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

Triode

Capacitance

  • Grid-to-plate capacitance

    3.2 pF

  • Input capacitance

    3.2 pF

  • Output capacitance

    2.2 pF

Other

  • Plate voltage

    100 V

    ClassA

  • Grid bias

    -5 V

    ClassA; PlateVoltage=100V

  • Plate current

    2.5 mA

    ClassA; PlateVoltage=100V

  • Plate voltage

    250 V

    ClassA

  • Grid bias

    -13.5 V

    ClassA; PlateVoltage=250V

  • Plate current

    5 mA

    ClassA; PlateVoltage=250V

  • Plate voltage

    45 V

    Detector; GridLeak

  • Grid leak resistance

    1 to 5 MOhm

    Detector; GridLeak

  • Grid condenser

    0.00025 uF

    Detector; GridLeak

Characteristic

  • Plate resistance

    12000 ohm

    ClassA; PlateVoltage=100V

  • Transconductance

    1150 uS

    ClassA; PlateVoltage=100V

  • Plate resistance

    9500 ohm

    ClassA; PlateVoltage=250V

  • Transconductance

    1450 uS

    ClassA; PlateVoltage=250V

Data set 02

193X Cunningham

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater/filament voltage

    2.5 V

    Published nominal

  • Heater/filament current

    1 A

    Published nominal

  • Transconductance

    1450 uS

    Published characteristic

  • Amplification factor

    13.8

    Published characteristic

  • Plate resistance

    9500 Ohm

    Published characteristic

Data set 03

1940 RCA

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • HeaterVoltageNominal

    2.5 V

    Nominal

  • HeaterCurrentNominal

    1 A

    Nominal

  • Maximum Plate Voltage

    250 V

  • Maximum Cathode Current

    10 mA

Characteristic

  • Transconductance

    1450 µS

    Typical

  • Amplification Factor

    13.8

    Typical

  • Plate Resistance

    9500 ohm

    Typical

Data set 04

195X General Electric Essential Characteristics

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Maximum plate voltage

    250 V

    Published handbook rating

  • Plate voltage

    250 V

    ClassA

  • Control-grid bias

    13.5 V

    ClassA

  • Plate current

    5 mA

    ClassA

Characteristic

  • Plate resistance

    9500 ohm

    Published handbook characteristic

  • Transconductance

    1460 µS

    Published handbook characteristic

  • Amplification factor

    13.8

    Published handbook characteristic

  • Heater/filament voltage

    2.5 V

    Published heater/filament rating

  • Heater/filament current

    1 A

    Published heater/filament rating

Data set 05

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater voltage

    2.5 V

  • Heater current

    1 A

  • Plate voltage

    250 V

    ClassA1

Characteristic

  • Plate current

    5 mA

    ClassA1

Capacitance

  • Grid-to-plate capacitance

    3.2 pF

  • Grid-to-cathode capacitance

    3.2 pF

  • Plate-to-cathode capacitance

    2.2 pF