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Voltage - Dual Triode (similar) ·Triode-Triode

8CG7

Medium-mu twin triode designed for television deflection timing, serving as a combined vertical- and horizontal-deflection oscillator in television receivers.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
9LP
Socket code
B9A
Base pins
9
Nominal heater
8.4 V / 450 mA

Description

Medium-mu twin triode used as combined vertical- and horizontal-deflection oscillator in television receivers.

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
9LP
Socket code
B9A
Base pins
9
Nominal heater voltage
8.4 V
Nominal heater current
450 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

9LP - 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
6700 Ω
Transconductance
0.003 S
Amplification factor
20
Max plate voltage
300 V
Max plate dissipation
3.5 W
Max cathode current
20 mA
Rectifier max heater-cathode voltage
200 V
Rectifier warm-up time
11 s

Published promoted fields populated semantically; identical repeated sections compressed.

Section 2

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
6700 Ω
Transconductance
0.003 S
Amplification factor
20
Max plate voltage
300 V
Max plate dissipation
3.5 W
Max cathode current
20 mA

Physical triode section added to align rows with SectionCount.

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

Characteristic

  • Plate Resistance

    7700 ohm

    AlternateOperatingPoint

  • Transconductance

    2600 uS

    AlternateOperatingPoint

Data set 02

1965 Sylvania Electronic Tubes Vol3

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Heater voltage

    8.4 V

    Rated heater condition

  • Heater current

    450 mA

    Rated heater condition

Other

  • Voltage(ocordc)

    8.4 V

    Voltage(ocordc) .......... 6.3 8.4 Volts Grid Voltage:

  • Warm-upTimeA

    11 s

    Warm-upTimeA ........... 11 11 Seconds Plate Dissipcltion:

Data set 03

1966 Tung Sol Electronic Tubes 2 of 4

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate_voltage

    250 V

    Section1,Section2,ClassA

  • Heater_warmup_time

    11 s

    Section1,Section2,ClassA

Characteristic

  • Plate_current

    9 mA

    Section1,Section2,ClassA

  • Plate_resistance

    7700 ohm

    Section1,Section2,ClassA

  • Amplification_factor

    20

    Section1,Section2,ClassA

  • Transconductance

    2600 uS

    Section1,Section2,ClassA

Data set 04

1971 RCA HB3 Binder 5 of 7

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater voltage nominal

    8.4 V

  • Heater current nominal

    450 mA

Data set 05

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater Voltage (ac/dc) 6.3 8.4

    12.6 V

    Published in approved 12FQ7 target entry; Section1

  • Heater Current 0.6 0.45

    300 mA

    Published in approved 12FQ7 target entry; Section1

  • Heater Warm-up Time (Average)

    11 seconds

    Published in approved 12FQ7 target entry; Section1

  • Grid to Plate 3.6

    3.8 pF

    Published in approved 12FQ7 target entry; Section1

  • Grid to Cathode and Heater 2.4

    2.4 pF

    Published in approved 12FQ7 target entry; Section1

  • Plate to Cathode and Heater 0.34

    0.26 pF

    Published in approved 12FQ7 target entry; Section1

  • Plate Voltage

    330 V

    Published in approved 12FQ7 target entry; Section1

  • Grid Voltage, Positive-bias value

    0 V

    Published in approved 12FQ7 target entry; Section1

  • Cathode Current

    22 mA

    Published in approved 12FQ7 target entry; Section1

  • For both plates with both units opex'ating

    5.7 W

    Published in approved 12FQ7 target entry; Section1

  • Plate Voltage 90

    250 V

    Published in approved 12FQ7 target entry; Section1

  • Grid Voltage 0

    -8 V

    Published in approved 12FQ7 target entry; Section1

  • Plate Resistance (Approx.) 6700

    7700 Ω

    Published in approved 12FQ7 target entry; Section1

  • DC Plate Voltage 330

    330 V

    Published in approved 12FQ7 target entry; Section1

  • Peak Negative-Pulse Grid Voltage 440

    660 V

    Published in approved 12FQ7 target entry; Section1

  • Peak Cathode Current 77

    330 mA

    Published in approved 12FQ7 target entry; Section1

  • Average Cathode Current 22

    22 mA

    Published in approved 12FQ7 target entry; Section1

  • For either plate 4

    4 W

    Published in approved 12FQ7 target entry; Section1

  • For both plates with both units operating . . . 5.7

    6.7 W

    Published in approved 12FQ7 target entry; Section1

  • Grid-Circuit Resistance 2.2

    2.2 MΩ

    Published in approved 12FQ7 target entry; Section1

  • Heater Voltage (ac/dc) 2.4 2.9

    6.3 V

    Published in approved 12FQ7 target entry; Section1

  • Heater Current 0.6 0.45

    200 mA

    Published in approved 12FQ7 target entry; Section1

  • Heater Warm-up Time (Average) 11

    11 seconds

    Published in approved 12FQ7 target entry; Section1

  • Plate Voltage

    300 V

    Published in approved 12FQ7 target entry; Section1

  • Grid-No.3 (Screen-Grid) Voltage

    150 V

    Published in approved 12FQ7 target entry; Section1

  • Negative-bias value

    60 V

    Published in approved 12FQ7 target entry; Section1

  • Positive-bias value

    0 V

    Published in approved 12FQ7 target entry; Section1

  • Cathode Current

    20 mA

    Published in approved 12FQ7 target entry; Section1

  • Plate Dissipation

    3.25 W

    Published in approved 12FQ7 target entry; Section1

  • Grid-No.3 Input

    0.16 W

    Published in approved 12FQ7 target entry; Section1

  • Plate Voltage

    275 V

    Published in approved 12FQ7 target entry; Section1

  • Grid-No.3 Voltage

    135 V

    Published in approved 12FQ7 target entry; Section1

  • Grid-No.l Voltage

    -0.2 V

    Published in approved 12FQ7 target entry; Section1

  • Grid-No.l-Circuit Resistance, for fixed-bias operation

    0.5 MΩ

    Published in approved 12FQ7 target entry; Section1

Capacitance

  • Plate of Unit No.l to Plate of Unit No

    2 pF

    Published in approved 12FQ7 target entry; Section1

  • Grid No.l to Plate 0.03

    0.016 pF

    Published in approved 12FQ7 target entry; Section1

  • No.3, and Grid No.4

    4.8 pF

    Published in approved 12FQ7 target entry; Section1

  • and Grid No

    4 pF

    Published in approved 12FQ7 target entry; Section1

Characteristic

  • Plate Current 10

    9 mA

    Published in approved 12FQ7 target entry; Section1

  • Grid Voltage (Approx.) for plate current of 10 /iA. —7

    -18 V

    Published in approved 12FQ7 target entry; Section1

  • 12.5 volts

    1.3 mA

    Published in approved 12FQ7 target entry; Section1

  • Plate Resistance (Approx. )

    0.24 MΩ

    Published in approved 12FQ7 target entry; Section1

  • Transconductance

    10000 µS

    Published in approved 12FQ7 target entry; Section1

  • Plate Current

    9 mA

    Published in approved 12FQ7 target entry; Section1

  • Grid-No.3 Current

    0.17 mA

    Published in approved 12FQ7 target entry; Section1

  • Grid-No.l Voltage (Approx.) for transconductance of

    100 µS

    Published in approved 12FQ7 target entry; Section1

  • Grid-No.l Voltage (Approx.) for transconductance of 100 /imhos

    -5 V

    Published in approved 12FQ7 target entry; Section1