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Voltage - Triode (single) ·Triode

37

Medium-mu receiving triode with a 6.3 V, 300 mA heater, intended for general voltage-amplifier and related small-signal service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
5A
Socket code
UX5
Base pins
5
Nominal heater
6.3 V / 300 mA

Description

37 is listed in the supplied receiving-tube handbook as a medium-mu triode. The published heater/filament rating is 6.3 V at 0.3 A.

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
6.3 V
Nominal heater current
300 mA
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
8400 Ω
Transconductance
0.0011 S
Amplification factor
9.2
Max plate voltage
180 V

Published ratings and characteristics promoted from the approved datasheet.

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

    2 pF

    Published direct interelectrode capacitance

  • Grid-cathode capacitance

    3.5 pF

    Published direct interelectrode capacitance

  • Plate-cathode capacitance

    2.2 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

    18 V

    ClassA

  • Plate current

    7.5 mA

    ClassA

Characteristic

  • Plate resistance

    8400 ohm

    Published datasheet characteristic

  • Transconductance

    1100 µS

    Published datasheet characteristic

  • Amplification factor

    9.2

    Published datasheet characteristic

  • Heater/filament voltage

    6.3 V

    Published heater/filament rating

  • Heater/filament current

    300 mA

    Published heater/filament rating

Capacitance

  • Input capacitance

    3.6 pF

    Published capacitance

  • Output capacitance

    2.2 pF

    Published capacitance

  • Grid-to-plate capacitance

    2 pF

    Published capacitance

Data set 03

193X Cunningham

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater/filament voltage

    6.3 V

    Published nominal

  • Heater/filament current

    300 mA

    Published nominal

  • Transconductance

    1100 uS

    Published characteristic

  • Amplification factor

    9.2

    Published characteristic

  • Plate resistance

    8400 Ohm

    Published characteristic

Data set 04

1940 RCA

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater or filament voltage

    6.3 V

    Published nominal value

  • Heater or filament current

    300 mA

    Published nominal value

  • Transconductance

    1100 µS

    Published representative/high operating value

  • Amplification factor

    9.2

    Published representative/high operating value

  • Plate resistance

    8400 ohm

    Published representative/high operating value

Capacitance

  • Grid-to-plate capacitance

    2 pF

    Published

  • Grid-to-cathode capacitance

    3.5 pF

    Published

  • Plate-to-cathode capacitance

    2.9 pF

    Published

Data set 05

1948 Brimar Radio Valve Manual

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • HeaterOrFilamentVoltage

    6.3 V

  • HeaterOrFilamentCurrent

    300 mA

Data set 06

1950 Sylvania

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • HeaterOrFilamentVoltage

    6.3 V

  • HeaterOrFilamentCurrent

    300 mA

Data set 07

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

    18 V

    ClassA

  • Plate current

    7.5 mA

    ClassA

Characteristic

  • Plate resistance

    8400 ohm

    Published handbook characteristic

  • Transconductance

    1100 µS

    Published handbook characteristic

  • Amplification factor

    9.2

    Published handbook characteristic

  • Heater/filament voltage

    6.3 V

    Published heater/filament rating

  • Heater/filament current

    300 mA

    Published heater/filament rating

Data set 08

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate voltage

    250 V

    ClassA

  • Plate current

    7.5 mA

    ClassA

  • Grid voltage

    -18 V

    ClassA