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Voltage Radio Detector Converter ·Pentode-Triode

6BR8A

Medium-mu triode plus sharp-cutoff pentode used as a combined oscillator and mixer in VHF television tuners.

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

Description

Reference/equivalence entry for a medium-mu triode plus sharp-cutoff pentode used as a combined oscillator and mixer in VHF television tuners.

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

9FA - Terminal pinout

Electrical assignments shared by every tube using this base designation.

TerminalSectionConnectionEvidence
PIN1Base PinBG1 — Control Grid

Original chart label: 2G1; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FA

PIN2Base PinBP — Plate (Anode)

Original chart label: 2P; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FA

PIN3Base PinBK — Cathode

Original chart label: 2K; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FA

PIN4Base Pin—H — Heater

Original chart label: H; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FA

PIN5Base Pin—H — Heater

Original chart label: H; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FA

PIN6Base PinAP — Plate (Anode)

Original chart label: 1P; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FA

PIN7Base PinAG2 — Screen Grid

Original chart label: 1G2; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FA

PIN8Base PinAG3 — Suppressor GridGroup 9FA8

Original chart label: 1G3; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FA

PIN8Base PinAK — CathodeGroup 9FA8

Original chart label: 1K; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FA

PIN8Base Pin—IS — Internal ScreenGroup 9FA8

Original chart label: IS; manufacturer verification pending

Unverified

EIA Base Connections, printed page 132, 9FA

Section ratings

2 physical sections, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Transconductance
0.0075 S
Amplification factor
40
Max plate voltage
330 V
Max plate dissipation
3 W

Published promoted values applied where applicable; additional table data retained as parameters.

Section 2

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
400000 Ω
Transconductance
0.005 S
Max plate voltage
330 V
Max screen voltage
330 V
Max plate dissipation
3 W

Published promoted values applied where applicable; additional table data retained as parameters.

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

1971 RCA HB3 Binder 4 of 7

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Voltage (AC or DC) — published value 1

    6.3 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Voltage (AC or DC) — published value 2

    6.3 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Voltage (AC or DC) — published value 3

    0.6 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Current — published value 1

    0

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Current — published value 2

    450

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Current — published value 3

    0.03

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Current — published value 4

    0.45

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Grid to plate — published value 1

    1.8 pF

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Grid to plate — published value 2

    1.8 pF

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Grid No.1 to plate — published value 1

    0 pF

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Grid No.1 to plate — published value 2

    2 pF

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Grid No.1 to plate — published value 3

    0.01 pF

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Triode Cathode to Heater — published value 1

    2.4 pF

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Triode Cathode to Heater — published value 2

    2.4 pF

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Pin 1 -Triode Grid

    1

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Pin 2 -Triode Plate

    2

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Pin 4 -Heater

    4

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Pin 5 -Heater

    5

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Plate Voltage — published value 1

    125 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Plate Voltage — published value 2

    125 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Grid No.2 Voltage

    10 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Plate Resistance (Approx.) — published value 1

    0.2

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Plate Resistance (Approx.) — published value 2

    2

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Transconductance — published value 1

    7500

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Transconductance — published value 2

    5000

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Plate Current — published value 1

    13.5 mA

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Plate Current — published value 2

    9.5 mA

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Grid-No.2 Current

    3.5 mA

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Grid-No.l Voltage (ADPfO% ) — published value 1

    -9 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Grid-No.l Voltage (ADPfO% ) — published value 2

    -9 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • for plate µA = 20

    20

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Plate Voltage — published value 1

    330 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Plate Voltage — published value 2

    330 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

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

    330 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Grid-No.l (Control -Grid) Voltage — published value 1

    0 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Grid-No.l (Control -Grid) Voltage — published value 2

    0 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • For grid-No.2 voltages up to 165 volts — published value 1

    165 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • For grid-No.2 voltages up to 165 volts — published value 2

    0.55 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • For grid-No.2 voltages between 165 and

    165 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Plate Dissipation — published value 1

    2.5

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Plate Dissipation — published value 2

    3

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • heater amperes = 0.450

    450 mA

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • b Ac heater volts = 6. 3, — published value 1

    6 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • b Ac heater volts = 6. 3, — published value 2

    3 V

    Published datasheet value; multiple values represent separate source-table limits or conditions.

Other

  • Heater negative with respect to cathode

    200 mA

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Heater positive with respect to cathode

    200 mA

    Published datasheet value; multiple values represent separate source-table limits or conditions.

SECTION 2

Pentode

Other

  • Pentode Grid No.l to Triode Plate — published value 1

    0.2 mA

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Pentode Grid No.l to Triode Plate — published value 2

    0.2 mA

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Pentode Plate to Triode Plate — published value 1

    0 mA

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Pentode Plate to Triode Plate — published value 2

    1 mA

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Pentode Plate to Triode Plate — published value 3

    0.02 mA

    Published datasheet value; multiple values represent separate source-table limits or conditions.

Characteristics

  • Pin 6 -Pentode Plate

    6

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Pin 7 -Pentode Grid No.2

    7

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Pin 8 -Pentode Cathode, Grid No.3, Internal Shiel;~T

    8

    Published datasheet value; multiple values represent separate source-table limits or conditions.

  • Pin 9 -Pentode Grid No.1

    9

    Published datasheet value; multiple values represent separate source-table limits or conditions.