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Voltage Pentode - Sharp Cutoff (single) ·Pentode

3CF6

Sharp-cutoff pentode for television IF amplification and VHF tuner RF service with controlled heater warm-up.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B7G
Base pins
7
Nominal heater
3.15 V / 600 mA

Description

Sharp-cutoff pentode used as a television IF amplifier to about 45 MHz and as an 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
-
Socket code
B7G
Base pins
7
Nominal heater voltage
3.15 V
Nominal heater current
600 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

1 physical section, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
300000 Ω
Transconductance
0.0078 S
Max plate voltage
330 V
Max screen voltage
330 V
Max plate dissipation
2.3 W
Max screen dissipation
0.55 W

Published section ratings promoted where explicitly available; additional source values retained in parameter rows.

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

Other

  • Plate voltage

    125 V

  • Screen-grid voltage

    125 V

  • Cathode bias resistor

    56 Ohm

  • Plate current

    12.5 mA

  • Screen-grid current

    3.7 mA

Characteristics

  • Plate resistance

    300000 Ohm

  • Transconductance

    7800 uS

  • Control-grid cutoff voltage

    -6 V

Capacitance

  • Grid-to-plate capacitance

    0.025 pF

    Unshielded

  • Input capacitance

    6.5 pF

    Unshielded

  • Output capacitance

    2 pF

    Unshielded

Data set 02

1971 RCA HB3 Binder 4 of 7

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristics

  • Current — published value 1

    0

    Published datasheet value; multiple numbers on a row represent separate source limits or conditions.

  • Current — published value 2

    600

    Published datasheet value; multiple numbers on a row represent separate source limits or conditions.

  • Current — published value 3

    0.04

    Published datasheet value; multiple numbers on a row represent separate source limits or conditions.

  • Voltage (ac or dc) at 0.600 A — published value 1

    0 V

    Published datasheet value; multiple numbers on a row represent separate source limits or conditions.

  • Voltage (ac or dc) at 0.600 A — published value 2

    0.6 V

    Published datasheet value; multiple numbers on a row represent separate source limits or conditions.

  • Voltage (ac or dc) at 0.600 A — published value 3

    3.15 V

    Published datasheet value; multiple numbers on a row represent separate source limits or conditions.

  • Warm-up Time (Average)

    11

    Published datasheet value; multiple numbers on a row represent separate source limits or conditions.

  • Heater~athode Voltage — published value 1

    0 V

    Published datasheet value; multiple numbers on a row represent separate source limits or conditions.

  • Heater~athode Voltage — published value 2

    0 V

    Published datasheet value; multiple numbers on a row represent separate source limits or conditions.

  • Current — published value 1

    0.6

    Published datasheet value; multiple numbers on a row represent separate source limits or conditions.

  • Current — published value 2

    0.04

    Published datasheet value; multiple numbers on a row represent separate source limits or conditions.

Data set 03

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • about

    45 MHz

    Published in approved 6CB6A target datasheet entry; Section1

  • Heater Voltage (ac/dc) 3.15 4.2

    6.3 V

    Published in approved 6CB6A target datasheet entry; Section1

  • Heater Current 0.6 0.45

    300 mA

    Published in approved 6CB6A target datasheet entry; Section1

  • Heater Warm-up Time (Average) 11 11

    11 seconds

    Published in approved 6CB6A target datasheet entry; Section1

  • Plate Voltage

    330 V

    Published in approved 6CB6A target datasheet entry; Section1

  • Grid-No.S (Suppressor-Grid) Voltage, Positive value

    0 V

    Published in approved 6CB6A target datasheet entry; Section1

  • Grid-No.2 Supply Voltage

    330 V

    Published in approved 6CB6A target datasheet entry; Section1

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

    0 V

    Published in approved 6CB6A target datasheet entry; Section1

  • For grid-No.2 voltages between 165 and

    330 V

    Published in approved 6CB6A target datasheet entry; Section1

  • Plate Supply Voltage

    125 V

    Published in approved 6CB6A target datasheet entry; Section1

  • Cathode-Sias Resistor

    56 Ω

    Published in approved 6CB6A target datasheet entry; Section1

  • Grid-No.2 Current

    3.7 mA

    Published in approved 6CB6A target datasheet entry; Section1

  • Grid-No.l VoJt&ge (Approx.) for plate current of 20 jiA

    -6.5 V

    Published in approved 6CB6A target datasheet entry; Section1

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

    2.8 mA

    Published in approved 6CB6A target datasheet entry; Section1

  • Grid-No.l Voltage (Approx.) for plate current of 2.8 mA

    -3 V

    Published in approved 6CB6A target datasheet entry; Section1

Capacitance

  • Grid No. 3. and Internal Shield 6.5

    6.6 pF

    Published in approved 6CB6A target datasheet entry; Section1