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Voltage Radio Detector Converter ·Pentode-Triode

7HG8

Medium-mu triode plus frame-grid sharp-cutoff pentode used as a combined oscillator/mixer and television IF/video amplifier.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
-
Socket code
B9A
Base pins
9
Nominal heater
8 V / 300 mA

Description

Medium-mu triode plus frame-grid sharp-cutoff pentode used as combined oscillator/mixer and television IF/video amplifier.

Socket description

Small-button Noval 9-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B9A
Base pins
9
Nominal heater voltage
8 V
Nominal heater current
300 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

2 physical sections, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
7200 Ω
Transconductance
0.0055 S
Amplification factor
17
Max plate voltage
125 V
Max plate dissipation
1.5 W
Max cathode current
16 mA

Triode oscillator section; operating data cross-referenced to 6HG8/ECF86.

Section 2

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
350000 Ω
Transconductance
0.012 S
Max plate voltage
250 V
Max screen voltage
150 V
Max plate dissipation
2 W
Max screen dissipation
0.5 W
Max cathode current
18 mA

Pentode mixer section; operating data cross-referenced to 6HG8/ECF86.

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

1963 Amperex Condensed

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate voltage

    100 V

    VHF TV tuner oscillator

  • Grid voltage

    -3 V

    VHF TV tuner oscillator

  • Plate current

    14 mA

    VHF TV tuner oscillator

SECTION 2

Pentode

Other

  • Plate voltage

    170 V

    VHF TV tuner mixer

  • Screen voltage

    150 V

    VHF TV tuner mixer

  • Grid voltage

    -1.5 V

    VHF TV tuner mixer

  • Plate current

    10 mA

    VHF TV tuner mixer

  • Screen current

    3.3 mA

    VHF TV tuner mixer

Characteristic

  • Grid-1 to grid-2 amplification factor

    60

    VHF TV tuner mixer

Data set 02

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • For fixed-bias operation 0.5

    0.25 MΩ

    Published in approved ECF86 target datasheet entry; Section1

  • For cathode-bias operation 1

    1 MΩ

    Published in approved ECF86 target datasheet entry; Section1

  • Heater Voltage (ac/dc) 5.3 6.3

    7.2 V

    Published in approved ECF86 target datasheet entry; Section1

  • Heater Current

    300 mA

    Published in approved ECF86 target datasheet entry; Section1

  • Plate Voltage 125

    250 V

    Published in approved ECF86 target datasheet entry; Section1

  • Grid-No.2 (Screen-Grid) Voltage

    150 V

    Published in approved ECF86 target datasheet entry; Section1

  • Plate Dissipation 1.5

    2 W

    Published in approved ECF86 target datasheet entry; Section1

  • Grid-No.2 Input

    0.5 W

    Published in approved ECF86 target datasheet entry; Section1

  • Plate Voltage 100

    170 V

    Published in approved ECF86 target datasheet entry; Section1

  • Grid-No.2 Voltage

    160 V

    Published in approved ECF86 target datasheet entry; Section1

  • Voltage —3

    -1.2 V

    Published in approved ECF86 target datasheet entry; Section1

  • Transconductance 5500

    12000 µS

    Published in approved ECF86 target datasheet entry; Section1

  • Plate Current 14

    10 mA

    Published in approved ECF86 target datasheet entry; Section1

  • Grid-No.2 Current

    3.3 mA

    Published in approved ECF86 target datasheet entry; Section1

  • For fixed-bias operation

    0.25 MΩ

    Published in approved ECF86 target datasheet entry; Section1

  • For cathode-bias operation 0.5

    0.5 MΩ

    Published in approved ECF86 target datasheet entry; Section1

  • amperes, 0.6; warm-up time (average),

    11 seconds

    Published in approved ECF86 target datasheet entry; Section1

  • Plate Voltage 330

    330 V

    Published in approved ECF86 target datasheet entry; Section1

  • Grid-No.2 (Screen-Grid) Supply Voltage

    330 V

    Published in approved ECF86 target datasheet entry; Section1

  • 0

    0 V

    Published in approved ECF86 target datasheet entry; Section1

  • Plate Dissipation 2.5

    2.5 W

    Published in approved ECF86 target datasheet entry; Section1

  • For grid-No.2 voltages up to

    165 V

    Published in approved ECF86 target datasheet entry; Section1

  • For grid-No.2 voltages between 165 and

    330 V

    Published in approved ECF86 target datasheet entry; Section1

Characteristic

  • Plate Resistance (Approx.)

    0.35 MΩ

    Published in approved ECF86 target datasheet entry; Section1

  • Plate Voltage 125

    125 V

    Published in approved ECF86 target datasheet entry; Section1

  • Grid-No.2 Voltage

    125 V

    Published in approved ECF86 target datasheet entry; Section1

  • Grid-No.l Voltage 1 —

    -1 V

    Published in approved ECF86 target datasheet entry; Section1

  • Plate Resistance (Approx.) 5000

    150000 Ω

    Published in approved ECF86 target datasheet entry; Section1

  • Transconductance 7000

    10000 µS

    Published in approved ECF86 target datasheet entry; Section1

  • Plate Current 12.5

    12 mA

    Published in approved ECF86 target datasheet entry; Section1

  • 20 iiA —

    -7 V

    Published in approved ECF86 target datasheet entry; Section1

SECTION 2

Pentode

Other

  • For fixed-bias operation 0.5

    0.25 MΩ

    Published in approved ECF86 target datasheet entry; Section2

  • For cathode-bias operation 1

    1 MΩ

    Published in approved ECF86 target datasheet entry; Section2

  • Heater Voltage (ac/dc) 5.3 6.3

    7.2 V

    Published in approved ECF86 target datasheet entry; Section2

  • Heater Current

    300 mA

    Published in approved ECF86 target datasheet entry; Section2

  • Plate Voltage 125

    250 V

    Published in approved ECF86 target datasheet entry; Section2

  • Grid-No.2 (Screen-Grid) Voltage

    150 V

    Published in approved ECF86 target datasheet entry; Section2

  • Plate Dissipation 1.5

    2 W

    Published in approved ECF86 target datasheet entry; Section2

  • Grid-No.2 Input

    0.5 W

    Published in approved ECF86 target datasheet entry; Section2

  • Plate Voltage 100

    170 V

    Published in approved ECF86 target datasheet entry; Section2

  • Grid-No.2 Voltage

    160 V

    Published in approved ECF86 target datasheet entry; Section2

  • Voltage —3

    -1.2 V

    Published in approved ECF86 target datasheet entry; Section2

  • Transconductance 5500

    12000 µS

    Published in approved ECF86 target datasheet entry; Section2

  • Plate Current 14

    10 mA

    Published in approved ECF86 target datasheet entry; Section2

  • Grid-No.2 Current

    3.3 mA

    Published in approved ECF86 target datasheet entry; Section2

  • For fixed-bias operation

    0.25 MΩ

    Published in approved ECF86 target datasheet entry; Section2

  • For cathode-bias operation 0.5

    0.5 MΩ

    Published in approved ECF86 target datasheet entry; Section2

  • amperes, 0.6; warm-up time (average),

    11 seconds

    Published in approved ECF86 target datasheet entry; Section2

  • Plate Voltage 330

    330 V

    Published in approved ECF86 target datasheet entry; Section2

  • Grid-No.2 (Screen-Grid) Supply Voltage

    330 V

    Published in approved ECF86 target datasheet entry; Section2

  • 0

    0 V

    Published in approved ECF86 target datasheet entry; Section2

  • Plate Dissipation 2.5

    2.5 W

    Published in approved ECF86 target datasheet entry; Section2

  • For grid-No.2 voltages up to

    165 V

    Published in approved ECF86 target datasheet entry; Section2

  • For grid-No.2 voltages between 165 and

    330 V

    Published in approved ECF86 target datasheet entry; Section2

Characteristic

  • Plate Resistance (Approx.)

    0.35 MΩ

    Published in approved ECF86 target datasheet entry; Section2

  • Plate Voltage 125

    125 V

    Published in approved ECF86 target datasheet entry; Section2

  • Grid-No.2 Voltage

    125 V

    Published in approved ECF86 target datasheet entry; Section2

  • Grid-No.l Voltage 1 —

    -1 V

    Published in approved ECF86 target datasheet entry; Section2

  • Plate Resistance (Approx.) 5000

    150000 Ω

    Published in approved ECF86 target datasheet entry; Section2

  • Transconductance 7000

    10000 µS

    Published in approved ECF86 target datasheet entry; Section2

  • Plate Current 12.5

    12 mA

    Published in approved ECF86 target datasheet entry; Section2

  • 20 iiA —

    -7 V

    Published in approved ECF86 target datasheet entry; Section2