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Voltage - Triode (single) ·Triode

27

General-purpose receiving triode for voltage amplification, detection, oscillator, or Class-A service as documented by the manufacturer.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
5A
Socket code
UX5
Base pins
5
Nominal heater
2.5 V / 1.75 A

Description

General-purpose triode for amplifier, detector, or oscillator service; manufactured as a replacement for older receivers.

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
1.75 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
9250 Ω
Transconductance
0.001 S
Amplification factor
9
Max plate voltage
275 V
Rectifier max heater-cathode voltage
90 V

Transconductance promoted from representative published operating point.

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

1932 Cunningham Radio Tubes

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Grid-plate capacitance

    3.3 pF

    Published direct interelectrode capacitance

Data set 02

1937 Raytheon Radio Receiving Tubes

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Maximum plate voltage

    250 V

    Published datasheet rating

  • Plate voltage

    250 V

    ClassA

  • Control-grid bias

    21 V

    ClassA

  • Plate current

    5.2 mA

    ClassA

Characteristic

  • Plate resistance

    9250 ohm

    Published datasheet characteristic

  • Transconductance

    975 µS

    Published datasheet characteristic

  • Amplification factor

    9

    Published datasheet characteristic

  • Heater/filament voltage

    2.5 V

    Published heater/filament rating

  • Heater/filament current

    1.75 A

    Published heater/filament rating

Capacitance

  • Input capacitance

    3.5 pF

    Published capacitance

  • Output capacitance

    3 pF

    Published capacitance

  • Grid-to-plate capacitance

    3.3 pF

    Published capacitance

Data set 03

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

    1.75 A

    Published nominal

  • Transconductance

    1100 uS

    Published characteristic

  • Amplification factor

    9

    Published characteristic

  • Plate resistance

    9000 Ohm

    Published characteristic

Data set 04

1940 RCA

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • HEeaTer VoLTaGE (A.C.or D.C).evvvvnnnnn

    2.5 V

    HEeaTer VoLTaGE (A.C.or D.C).evvvvnnnnn.. 2.5 Volts

  • HEATER CURRENT ...ivvtiiniiintnennnnnnnnnns

    1.75 A

    HEATER CURRENT ...ivvtiiniiintnennnnnnnnnns 1.75 Amperes

  • PLATE VOLTAGE*

    250 V

    PLATE VOLTAGE* .......... 90 135 180 250 Volts

  • GRID VOLTAGE} ............ )

    -21 V

    GRID VOLTAGE} ............ ) -9 -13.5 -21 Volts

  • PLATE CURRENT

    5.2

    PLATE CURRENT ........... 2.7 4.5 5.0 5.2 Milliamperes

  • AMPLIFICATION FACTOR

    9

    AMPLIFICATION FACTOR ..... 9 9 9 9

  • * Maximum plate voltage =

    275 V

    * Maximum plate voltage = 275 volts,

  • t Maximum value of d-c resistance in grid circuit is

    1

    t Maximum value of d-c resistance in grid circuit is 1.0 megohm.

  • As an amplifier, the

    27

    As an amplifier, the 27 is applicable to the audio- or the radio-frequency

  • or with grid bias, The plate voltage for grid leak and condenser detection is

    45

    or with grid bias, The plate voltage for grid leak and condenser detection is 45

  • volts. A grid leak of from

    0.00025 V

    volts. A grid leak of from 1 to 5 megohms used with a grid condenser of 0.00025

  • uf is suitable. Por grid-bias detection, a plate voltage of

    275 V

    uf is suitable. Por grid-bias detection, a plate voltage of 275 volts or less may be

  • when no signal is being received, is approximately

    0.2

    when no signal is being received, is approximately 0.2 milliampere. For the

  • condition of

    250 V

    condition of 250 volts on plate and transformer coupling, the grid bias will be

  • approximately —~

    30 V

    approximately —~30 volts.

  • ° f E

    25 V

    ° f E5=25 VOLTS

  • PLATE VOLTS

    3 V

    PLATE VOLTS 92C—5I13R2

Characteristic

  • PLATE RESISTANCE ....,

    9250 ohm

    PLATE RESISTANCE ....,.... 11000 9000 9000 9250 Ohms

  • TRANSCONDUCTANCE

    975 µS

    TRANSCONDUCTANCE ........ 820 1000 1000 975 Micromhos

Data set 05

1948 Brimar Radio Valve Manual

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • HeaterOrFilamentVoltage

    2.5 V

  • HeaterOrFilamentCurrent

    1.75 A

Data set 06

1950 Sylvania

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Tension de chauffage CA ... ... ... .. .. .. 2,5 volts

    2.5 V

    Tension de chauffage CA ... ... ... .. .. .. 2,5 volts

  • Courant de chauffage ... ... ... .. ... .. .. 1,75 ampére

    1.75 A

    Courant de chauffage ... ... ... .. ... .. .. 1,75 ampére

  • Tension de chauffage ... 2,5 2,5 2,5 2,5 volts

    2.5 V

    Tension de chauffage ... 2,5 2,5 2,5 2,5 volts

  • Tension plaque ... .. .. 90 135 180 250 volts

    250 V

    Tension plaque ... .. .. 90 135 180 250 volts

  • Tension grille ... ... .. —6 —9 —13,5 —21 volts

    21 V

    Tension grille ... ... .. —6 —9 —13,5 —21 volts

  • Courant plaque ... .. 3 4,7 5,0 5.2 ma.

    5.2 ma

    Courant plaque ... .. 3 4,7 5,0 5.2 ma.

  • Résistance interne ... ... 10.000 9.000 9.000 9.250 ohms

    9.25 ohms

    Résistance interne ... ... 10.000 9.000 9.000 9.250 ohms

Data set 07

195X General Electric Essential Characteristics

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Maximum plate voltage

    275 V

    Published handbook rating

  • Plate voltage

    250 V

    ClassA

  • Control-grid bias

    21 V

    ClassA

  • Plate current

    5.2 mA

    ClassA

Characteristic

  • Plate resistance

    9250 ohm

    Published handbook characteristic

  • Transconductance

    975 µS

    Published handbook characteristic

  • Amplification factor

    9

    Published handbook characteristic

  • Heater/filament voltage

    2.5 V

    Published heater/filament rating

  • Heater/filament current

    1.75 A

    Published heater/filament rating

Capacitance

  • Input capacitance

    3.1 pF

    Published capacitance column

  • Output capacitance

    2.3 pF

    Published capacitance column

  • Grid-to-plate capacitance

    3.3 pF

    Published capacitance column

Data set 08

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate Voltage

    250 V

    Typical