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Voltage - Triode (single high frequency) ·Triode

3GK5

High-mu frame-grid miniature triode used as a grounded-cathode RF amplifier in VHF television tuners.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
7FP
Socket code
B7G
Base pins
7
Nominal heater
2.8 V / 450 mA

Description

High-mu frame-grid miniature triode used as a grounded-cathode RF amplifier in VHF television tuners.

Socket description

Miniature 7-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
7FP
Socket code
B7G
Base pins
7
Nominal heater voltage
2.8 V
Nominal heater current
450 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

7FP - Terminal pinout

Electrical assignments shared by every tube using this base designation.

TerminalSectionConnectionEvidence
PIN1KAK — Cathode

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 129, 7FP

PIN2G1AG1 — Control Grid

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 129, 7FP

PIN3H—H — Heater

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 129, 7FP

PIN4H—H — Heater

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 129, 7FP

PIN5PAP — Plate (Anode)

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 129, 7FP

PIN6ISAIS — Internal Screen

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 129, 7FP

PIN7KAK — Cathode

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 129, 7FP

Section ratings

1 physical section, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
5400 Ω
Transconductance
0.015 S
Amplification factor
78
Max plate voltage
200 V
Max plate dissipation
2.5 W
Max cathode current
22 mA

Sparse-source exception: representative section row; this sheet does not reproduce the electrical ratings/characteristics of 6GK5; no external values imported.

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

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Triode

Capacitance

  • GRID TO PLATE

    0.52 PF

    Published datasheet value

  • INPUT: G-TO (H + K+ 1.S. + E.S. )

    5 PF

    Published datasheet value

  • OUTPUT: P TO (H+ K +1.5. + E.S. )

    3.5 PF

    Published datasheet value

Other

  • HEATER TO CATHODE

    2.5 PF

    Published datasheet value

  • PLATE VOLTAGE

    200 VOLTS

    Published datasheet value

  • GRID VOLTAGE

    -50 VOLTS

    Published datasheet value

  • DC CATHODE CURRENT

    22 MA

    Published datasheet value

  • PLATE VOLTAGE

    135 VOLTS

    Published datasheet value

  • PLATE CURRENT

    1.5 MA

    Published datasheet value

  • HOT INPUT RESISTANCE - 200 Mc/s - GROUNDED PLATE

    275 OHMS

    Published datasheet value

Data set 02

1963 Amperex Condensed

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate voltage

    135 V

    VHFAmplifier

  • Control-grid voltage

    -1 V

    VHFAmplifier

  • Plate current

    11 mA

    VHFAmplifier

Characteristic

  • Plate resistance

    5200 Ω

    Section1

  • Transconductance

    13000 µS

    Section1

  • Amplification factor

    70

    Section1

Data set 03

1965 Sylvania Electronic Tubes Vol3

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate voltage

    135 V

  • Grid voltage

    -1 V

  • Plate current

    11.5 mA

Characteristics

  • Plate resistance

    5400 Ohm

  • Transconductance

    15000 uS

  • Amplification factor

    78 ratio

  • Hot input resistance

    275 Ohm

  • Noise figure

    4.7 dB

Capacitance

  • Hot input capacitance

    11.2 pF

Data set 04

1966 Tung Sol Electronic Tubes 1 of 4

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate voltage

    135 V

    VHFRFAmplifier

  • Grid voltage

    -1 V

    VHFRFAmplifier

  • Plate current

    11.5 mA

    VHFRFAmplifier

  • Application

    Frame-grid gain-controlled VHF RF amplifier

    Section1

Characteristic

  • Transconductance

    15000 µS

    Section1

  • Amplification factor

    78

    Section1

  • Plate resistance

    5400 Ω

    Section1

  • Grid voltage at 150 uS transconductance

    -4.2 V

    Section1

  • Noise figure at 200 MHz

    4.7 dB

    Section1

Data set 05

1968 General Electric Co

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater warm-up time

    11 s

Data set 06

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater Voltage (ac/dc) 2.3 2.8 4

    6.3 V

    Published in approved 2GK5 target datasheet entry; Section1

  • Heater Current 0.6 0.45 0.3

    180 mA

    Published in approved 2GK5 target datasheet entry; Section1

  • Negative-bias value

    50 V

    Published in approved 2GK5 target datasheet entry; Section1

  • Positive-bias value

    0 V

    Published in approved 2GK5 target datasheet entry; Section1

  • Average Cathode Current

    22 mA

    Published in approved 2GK5 target datasheet entry; Section1

  • Plate Dissipation

    2.5 W

    Published in approved 2GK5 target datasheet entry; Section1

  • Plate Voltage

    135 V

    Published in approved 2GK5 target datasheet entry; Section1

  • Grid Voltage

    -1 V

    Published in approved 2GK5 target datasheet entry; Section1

  • Plate Resistance (Approx.)

    5400 Ω

    Published in approved 2GK5 target datasheet entry; Section1

  • Transconductan'*.e

    15000 µS

    Published in approved 2GK5 target datasheet entry; Section1

  • Plate Current

    11.5 mA

    Published in approved 2GK5 target datasheet entry; Section1

  • Grid-Circuit Resistance, for cathode-bias operation

    1 MΩ

    Published in approved 2GK5 target datasheet entry; Section1

  • • Measured at

    200 MHz

    Published in approved 2GK5 target datasheet entry; Section1

  • f For a neutralized triode amplifier at a frequency of

    200 MHz

    Published in approved 2GK5 target datasheet entry; Section1

  • Heater Voltage (ac/dc) 6.3 10

    16 V

    Published in approved 2GK5 target datasheet entry; Section1

  • Heater Current 0.76 0.45

    300 mA

    Published in approved 2GK5 target datasheet entry; Section1

  • 11

    11 seconds

    Published in approved 2GK5 target datasheet entry; Section1

  • Plate Supply Voltage

    605 V

    Published in approved 2GK5 target datasheet entry; Section1

  • Plate Voltage

    330 V

    Published in approved 2GK5 target datasheet entry; Section1

  • Grid-No.2 Supply Voltage

    605 V

    Published in approved 2GK5 target datasheet entry; Section1

  • Grid-No.2 (Screen-Grid) Voltage

    330 V

    Published in approved 2GK5 target datasheet entry; Section1

  • Grid-No.l (Control-Grid) Voltage, Negative-bias value

    100 V

    Published in approved 2GK5 target datasheet entry; Section1

  • Cathode Current

    65 mA

    Published in approved 2GK5 target datasheet entry; Section1

  • Plate Dissipation

    13.2 W

    Published in approved 2GK5 target datasheet entry; Section1

  • Grid-No.2 Input, Peak

    4 W

    Published in approved 2GK5 target datasheet entry; Section1

  • Grid-No.2 Input, Average

    2 W

    Published in approved 2GK5 target datasheet entry; Section1

  • Plate Supply Voltage

    250 V

    Published in approved 2GK5 target datasheet entry; Section1

  • Grid-No.2 Supply Voltage

    250 V

    Published in approved 2GK5 target datasheet entry; Section1

  • Cathode-Bias Resistor

    135 Ω

    Published in approved 2GK5 target datasheet entry; Section1

  • Plate Resistance (Approx.)

    38000 Ω

    Published in approved 2GK5 target datasheet entry; Section1

  • Transconductance

    11300 µS

    Published in approved 2GK5 target datasheet entry; Section1

  • Peak AF Grid-No.l Voltage

    7.3 V

    Published in approved 2GK5 target datasheet entry; Section1

  • Zero-Signal Plate Current

    48 mA

    Published in approved 2GK5 target datasheet entry; Section1

  • Maximum-Signal Plate Current

    50.6 mA

    Published in approved 2GK5 target datasheet entry; Section1

  • Zero-Signal Grid-No.2 Current

    5.5 mA

    Published in approved 2GK5 target datasheet entry; Section1

  • Maximum-Signal Grid-No.2 Current

    10 mA

    Published in approved 2GK5 target datasheet entry; Section1

  • Effective Load Resistance

    5200 Ω

    Published in approved 2GK5 target datasheet entry; Section1

Capacitance

  • Grid to Plate

    0.62 pF

    Published in approved 2GK5 target datasheet entry; Section1

  • Grid to Cathode, Heater, and Internal Shield

    5 pF

    Published in approved 2GK5 target datasheet entry; Section1

  • Plate to Cathode, Heater, and Internal Shield

    3.5 pF

    Published in approved 2GK5 target datasheet entry; Section1

  • Internal Shield

    10 pF

    Published in approved 2GK5 target datasheet entry; Section1

  • Internal Shield

    7 pF

    Published in approved 2GK5 target datasheet entry; Section1

Characteristic

  • Input Resistance*

    275 Ω

    Published in approved 2GK5 target datasheet entry; Section1

  • Input Capacitance*

    11.2 pF

    Published in approved 2GK5 target datasheet entry; Section1

  • Grid Voltage (Approx.) for transconductance of

    1500 µS

    Published in approved 2GK5 target datasheet entry; Section1

  • Grid Voltage (Approx.) for transconductance of 1500 /imhos

    -2.5 V

    Published in approved 2GK5 target datasheet entry; Section1