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Voltage Pentode - Remote Cutoff (single) ·Pentode

6K7GT

GT-envelope variable-mu RF pentode for RF and IF amplification. Its gradual cutoff characteristic supports automatic gain control in receiver signal stages while retaining the compact tubular-glass format.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
7R
Socket code
IO
Base pins
8
Nominal heater
6.3 V / 300 mA

Description

Vari-mu RF pentode for RF and IF amplification.

Socket description

International Octal

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
7R
Socket code
IO
Base pins
8
Nominal heater voltage
6.3 V
Nominal heater current
300 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

7R - Terminal pinout

Electrical assignments shared by every tube using this base designation.

TerminalSectionConnectionEvidence
PIN1SHASH — Internal Shield

EIA chart transcription; independent manufacturer verification pending

Unverified

EIA Base Connections, printed page 128, 7R

PIN2H—H — Heater

EIA chart transcription; independent manufacturer verification pending

Unverified

EIA Base Connections, printed page 128, 7R

PIN3PAP — Plate (Anode)

EIA chart transcription; independent manufacturer verification pending

Unverified

EIA Base Connections, printed page 128, 7R

PIN4G2AG2 — Screen Grid

EIA chart transcription; independent manufacturer verification pending

Unverified

EIA Base Connections, printed page 128, 7R

PIN5G3AG3 — Suppressor Grid

EIA chart transcription; independent manufacturer verification pending

Unverified

EIA Base Connections, printed page 128, 7R

PIN7H—H — Heater

EIA chart transcription; independent manufacturer verification pending

Unverified

EIA Base Connections, printed page 128, 7R

PIN8KAK — Cathode

EIA chart transcription; independent manufacturer verification pending

Unverified

EIA Base Connections, printed page 128, 7R

CAP1G1AG1 — Control Grid

EIA chart transcription; independent manufacturer verification pending

Unverified

EIA Base Connections, printed page 128, 7R

Section ratings

1 physical section, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
600000 Ω
Transconductance
0.00165 S
Amplification factor
990
Max plate voltage
300 V
Max screen voltage
125 V
Max plate dissipation
2.75 W
Max screen dissipation
0.3 W

Published ratings and characteristics promoted where clearly legible in the approved source.

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

1948 Brimar Radio Valve Manual

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristics

  • Cutoff characteristic

    Variable-mu

Data set 02

1958 Brimar Radio Valve No 7

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristics

  • Cutoff characteristic

    Variable-mu

Application

  • Application

    RF / IF amplification

Data set 03

195X General Electric Essential Characteristics

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Maximum plate voltage

    300 V

    Published handbook rating

  • Maximum screen voltage

    150 V

    Published handbook rating

  • Plate voltage

    250 V

    ClassA

  • Screen voltage

    125 V

    ClassA

  • Control-grid bias

    3 V

    ClassA

  • Plate current

    10.5 mA

    ClassA

  • Screen current

    2.6 mA

    ClassA

Characteristic

  • Plate resistance

    600000 ohm

    Published handbook characteristic

  • Transconductance

    1650 µS

    Published handbook characteristic

  • Heater voltage

    6.3 V

    Published heater rating

  • Heater current

    300 mA

    Published heater rating

Capacitance

  • Input capacitance

    5 pF

    Published capacitance column

  • Output capacitance

    12 pF

    Published capacitance column

  • Grid-to-plate capacitance

    0.007 pF

    Published capacitance column

Data set 04

1961 Ferranti Technical Handbook

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate voltage

    100 V

    Point1

  • Screen-grid voltage

    100 V

    Point1

  • Control-grid voltage

    -1 V

    Point1

  • Plate current

    9.5 mA

    Point1

  • Screen-grid current

    2.7 mA

    Point1

  • Plate voltage

    250 V

    Point3

  • Screen-grid voltage

    125 V

    Point3

  • Plate current

    10.5 mA

    Point3

Characteristics

  • Transconductance

    1650 uS

    Point1

  • Plate resistance

    150000 Ohm

    Point1

  • Control-grid cutoff voltage

    -38 V

    Point1

  • Transconductance

    1650 uS

    Point3

  • Plate resistance

    600000 Ohm

    Point3

  • Control-grid cutoff voltage

    -52 V

    Point3

Capacitance

  • Input capacitance

    5 pF

    6K7G

  • Input capacitance

    4.6 pF

    6K7GT

  • Output capacitance

    12 pF

  • Grid-to-plate capacitance maximum

    0.007 pF

    6K7G

  • Grid-to-plate capacitance maximum

    0.005 pF

    6K7GT

Data set 05

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate Voltage

    250 V

    Average characteristics

  • Screen Voltage

    125 V

    Average characteristics

Characteristic

  • Plate Current

    10.5 mA

    Average characteristics

  • Screen Current

    2.6 mA

    Average characteristics