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Voltage Pentode - Sharp Cutoff (single) ·Pentode

7543

Sharp-cutoff pentode optimized for low-hum, low-microphony resistance-coupled voltage amplification in compact audio equipment.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
76K
Socket code
B7G
Base pins
7
Nominal heater
6.3 V / 300 mA

Description

Sharp-cutoff pentode for compact audio equipment; source states electrical identity with 6AU6A except for controlled hum characteristics.

Socket description

Miniature 7-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
76K
Socket code
B7G
Base pins
7
Nominal heater voltage
6.3 V
Nominal heater current
300 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

76K - 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

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
1000000 Ω
Transconductance
0.0052 S
Max plate voltage
300 V
Max screen voltage
300 V
Max plate dissipation
3 W
Max screen dissipation
0.65 W

Published electrical section from supplied RCA data sheet.

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

1965 Sylvania Electronic Tubes Vol3

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristics

  • Heater voltage

    6.3 V

  • Heater current

    300 mA

  • Transconductance

    5200 uS

  • Amplification factor triode connected

    36

    TriodeConnection

  • Plate resistance

    1 Mohm

  • Hum at plate typical

    1.2 mV

Other

  • Heater-cathode voltage maximum heater negative

    200 V

  • Heater-cathode voltage maximum heater positive DC

    100 V

  • Typical plate voltage

    250 V

  • Typical grid2 voltage

    150 V

Capacitance

  • Grid1-to-plate capacitance maximum

    0.0035 pF

  • Input capacitance

    5.5 pF

  • Output capacitance

    5 pF

  • Triode-connected grid-to-plate capacitance

    2.6 pF

    TriodeConnection

CrossReference

  • Equivalent type

    6AU6

Application

  • Application

    Low-hum voltage amplifier

Data set 02

1971 RCA HB3 Binder 5 of 7

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Heater voltage nominal

    6.3 V

  • Heater current nominal

    300 mA

  • Voltage (AC or DC)

    6.3 V

    Published source row

  • Current o•

    300 mA

    Published source row

  • PLATE VOLTAGE

    250 V

    Published source row

  • PLATE VOLTAGE (value 2)

    300 V

    Published source row

  • GRID-No

    2

    Published source row

  • SUPPLY VOLTAGE

    300 V

    Published source row

  • GRID-No

    2 A

    Published source row

  • GRID-No

    2

    Published source row

  • For grid-No

    2

    Published source row

  • For grid-No

    2

    Published source row

  • PLATE DISSIPATION

    3.2 W

    Published source row

  • PLATE DISSIPATION (value 2)

    3 W

    Published source row

Capacitance

  • cathode resistor )ohms) =

    1000

    Published source row

Characteristics

  • Plate Supply Voltage

    100 V

    Published source row

  • Plate Supply Voltage (value 2)

    250 V

    Published source row

  • Plate Supply Voltage (value 3)

    250 V

    Published source row

  • Grid-No

    2 V

    Published source row

  • Grid-No (value 2)

    100 V

    Published source row

  • Grid-No (value 3)

    125 V

    Published source row

  • Cathode Resistor

    150 ohm

    Published source row

  • Cathode Resistor (value 2)

    100 ohm

    Published source row

  • Cathode Resistor (value 3)

    68 ohm

    Published source row

  • Plate Resistance (Approx )

    5 Mohm

    Published source row

  • Plate Resistance (Approx ) (value 2)

    1.5 Mohm

    Published source row

  • Plate Resistance (Approx ) (value 3)

    1 Mohm

    Published source row

  • Transconductance

    3900

    Published source row

  • Transconductance (value 2)

    4500

    Published source row

  • Transconductance (value 3)

    5200

    Published source row

  • Plate Current

    5 mA

    Published source row

  • Plate Current (value 2)

    7.6 mA

    Published source row

  • Plate Current (value 3)

    10.6 mA

    Published source row

  • Grid-No

    2 mA

    Published source row

  • Grid-No (value 2)

    21 mA

    Published source row

  • Grid-No (value 3)

    3 mA

    Published source row

  • Plate Supply Voltage

    250 V

    Published source row

  • Cathode Resistor

    330 ohm

    Published source row

  • Amplification Factor

    36

    Published source row

  • Plate Resistance (Approx )

    7500 ohm

    Published source row

  • Transconductance

    4800

    Published source row

  • Plate Current

    12.2 mA

    Published source row

Data set 03

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • Hum Output Voltage

    1.2 mV

    CathodeBypassed;RMS

  • Hum Output Voltage

    0.9 mV

    CathodeUnbypassed;RMS