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Voltage Radio Detector Converter ·Pentode-Triode

4BL8

Medium-mu triode plus sharp-cutoff pentode used as a television frequency changer.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
9DC
Socket code
B9A
Base pins
9
Nominal heater
4.6 V / 600 mA

Description

Medium-mu triode plus sharp-cutoff pentode used in television frequency-changer service.

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
9DC
Socket code
B9A
Base pins
9
Nominal heater voltage
4.6 V
Nominal heater current
600 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

9DC - Terminal pinout

Electrical assignments shared by every tube using this base designation.

TerminalSectionConnectionEvidence
PIN12PBP — Plate (Anode)

Chart transcription; manufacturer verification pending

Unverified

EIA Base Connections, printed page 131, 9DC

PIN21G1AG1 — Control Grid

Chart transcription; manufacturer verification pending

Unverified

EIA Base Connections, printed page 131, 9DC

PIN31G2AG2 — Screen Grid

Chart transcription; manufacturer verification pending

Unverified

EIA Base Connections, printed page 131, 9DC

PIN4H—H — Heater

Chart transcription; manufacturer verification pending

Unverified

EIA Base Connections, printed page 131, 9DC

PIN5H—H — Heater

Chart transcription; manufacturer verification pending

Unverified

EIA Base Connections, printed page 131, 9DC

PIN61PAP — Plate (Anode)

Chart transcription; manufacturer verification pending

Unverified

EIA Base Connections, printed page 131, 9DC

PIN71G3AG3 — Suppressor GridGroup 9DC7

Chart transcription; manufacturer verification pending

Unverified

EIA Base Connections, printed page 131, 9DC

PIN7ISAIS — Internal ScreenGroup 9DC7

Chart transcription; manufacturer verification pending

Unverified

EIA Base Connections, printed page 131, 9DC

PIN71KAK — CathodeGroup 9DC7

Chart transcription; manufacturer verification pending

Unverified

EIA Base Connections, printed page 131, 9DC

PIN82KBK — Cathode

EIA chart transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 131, 9DC

PIN92G1BG1 — Control Grid

EIA chart transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 131, 9DC

Section ratings

2 physical sections, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
400000 Ω
Transconductance
0.005 S
Max plate voltage
250 V
Max screen voltage
200 V
Max plate dissipation
1.7 W
Max screen dissipation
0.75 W
Max cathode current
14 mA
Rectifier max heater-cathode voltage
200 V

Published ratings and characteristics promoted where applicable.

Section 2

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
12500 Ω
Transconductance
0.005 S
Amplification factor
20
Max plate voltage
250 V
Max plate dissipation
1.7 W
Max cathode current
14 mA
Rectifier max heater-cathode voltage
200 V

Published ratings and characteristics promoted where applicable.

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

1966 Tung Sol Electronic Tubes 1 of 4

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate voltage

    170 V

    Mixer

  • Screen voltage

    170 V

    Mixer

  • Plate current

    10 mA

    Mixer

  • Screen current

    2.8 mA

    Mixer

Characteristic

  • Transconductance

    6200 µS

    Section2

  • Plate resistance

    400000 Ω

    Section2

SECTION 2

Triode

Other

  • Plate voltage

    100 V

    Oscillator

  • Plate current

    12 mA

    Oscillator

Characteristic

  • Transconductance

    5500 µS

    Section1

  • Amplification factor

    20

    Section1

Data set 02

1971 RCA HB3 Binder 4 of 7

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate Voltage

    170 V

    Inherited from explicitly referenced 6-volt parent type; heater variant

  • Screen Voltage

    170 V

    Inherited from explicitly referenced 6-volt parent type; heater variant

  • Grid Voltage

    -2 V

    Inherited from explicitly referenced 6-volt parent type; heater variant

  • Plate Current

    10 mA

    Inherited from explicitly referenced 6-volt parent type; heater variant

  • Screen Current

    2.8 mA

    Inherited from explicitly referenced 6-volt parent type; heater variant

Characteristics

  • Plate Resistance

    400000 Ω

    Inherited from explicitly referenced 6-volt parent type; heater variant

  • Transconductance

    6200 µS

    Inherited from explicitly referenced 6-volt parent type; heater variant

SECTION 2

Triode

Other

  • Heater Current

    560 mA to 640 mA

    Published nominal ± tolerance

  • Heater Voltage

    4.6 V

    At heater current 0.6 A

  • Plate Voltage

    100 V

    Inherited from explicitly referenced 6-volt parent type; heater variant

  • Grid Voltage

    -2 V

    Inherited from explicitly referenced 6-volt parent type; heater variant

  • Plate Current

    14 mA

    Inherited from explicitly referenced 6-volt parent type; heater variant

Characteristics

  • Amplification Factor

    20

    Inherited from explicitly referenced 6-volt parent type; heater variant

  • Transconductance

    5000 µS

    Inherited from explicitly referenced 6-volt parent type; heater variant

Data set 03

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • • Pulse duration must not exceed 15% of a vertical scanning cycle (

    2.5 milliseconds

    Published in approved ECF80 target datasheet entry; Section2

  • Heater Voltage (ac/dc) 4.6

    6.3 V

    Published in approved ECF80 target datasheet entry; Section2

  • Heater Current 0.6

    450 mA

    Published in approved ECF80 target datasheet entry; Section2

  • Plate Supply Voltage 550

    550 V

    Published in approved ECF80 target datasheet entry; Section2

  • Plate Voltage 250

    250 V

    Published in approved ECF80 target datasheet entry; Section2

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

    550 V

    Published in approved ECF80 target datasheet entry; Section2

  • With cathode current of

    14 mA

    Published in approved ECF80 target datasheet entry; Section2

  • With cathode current of 14 mA

    175 V

    Published in approved ECF80 target datasheet entry; Section2

  • With cathode current less than

    10 mA

    Published in approved ECF80 target datasheet entry; Section2

  • With cathode current less than 10 mA

    200 V

    Published in approved ECF80 target datasheet entry; Section2

  • Cathode Current 14

    14 mA

    Published in approved ECF80 target datasheet entry; Section2

  • Plate Dissipation 1.5

    1.7 W

    Published in approved ECF80 target datasheet entry; Section2

  • With plate dissipation greater than

    1.2 W

    Published in approved ECF80 target datasheet entry; Section2

  • With plate dissipation greater than 1.2 watts

    0.5 W

    Published in approved ECF80 target datasheet entry; Section2

  • With p.late dissipation less than

    1.2 W

    Published in approved ECF80 target datasheet entry; Section2

  • Input Resistance at frequency of

    50 MHz

    Published in approved ECF80 target datasheet entry; Section2

  • Equivalent Noise Resistance

    1500 Ω

    Published in approved ECF80 target datasheet entry; Section2

  • For fixed-bias operation 0.5

    0.5 MΩ

    Published in approved ECF80 target datasheet entry; Section2

  • For cathode-bias operation 0.5

    1 MΩ

    Published in approved ECF80 target datasheet entry; Section2

  • Heater Voltage 6.3

    50 V

    Published in approved ECF80 target datasheet entry; Section2

  • Heater Current 0.78

    100 mA

    Published in approved ECF80 target datasheet entry; Section2

  • Plate Supply Voltage 550

    900 V

    Published in approved ECF80 target datasheet entry; Section2

  • Plate Voltage 300

    600 V

    Published in approved ECF80 target datasheet entry; Section2

  • Grid-No.2 Supply Voltage

    550 V

    Published in approved ECF80 target datasheet entry; Section2

  • Plate Dissipation 1

    7 W

    Published in approved ECF80 target datasheet entry; Section2

  • Grid-No.2 Input

    1.8 W

    Published in approved ECF80 target datasheet entry; Section2

  • Plate Voltage 100

    200 V

    Published in approved ECF80 target datasheet entry; Section2

  • For fixed-bias operation I

    1 MΩ

    Published in approved ECF80 target datasheet entry; Section2

  • For cathode-bias operation 2

    2 MΩ

    Published in approved ECF80 target datasheet entry; Section2

Characteristic

  • Plate Voltage 100

    170 V

    Published in approved ECF80 target datasheet entry; Section2

  • Transconductance 5000

    6200 µS

    Published in approved ECF80 target datasheet entry; Section2

  • Plate Current 14

    10 mA

    Published in approved ECF80 target datasheet entry; Section2

  • Plate Resistance (Approx.)

    0.02 MΩ

    Published in approved ECF80 target datasheet entry; Section2

  • Transconductance 2500

    6400 µS

    Published in approved ECF80 target datasheet entry; Section2

  • Plate Current 3.5

    35 mA

    Published in approved ECF80 target datasheet entry; Section2

  • Grid-No.2 Current

    7 mA

    Published in approved ECF80 target datasheet entry; Section2

SECTION 2

Triode

Other

  • • Pulse duration must not exceed 15% of a vertical scanning cycle (

    2.5 milliseconds

    Published in approved ECF80 target datasheet entry; Section1

  • Heater Voltage (ac/dc) 4.6

    6.3 V

    Published in approved ECF80 target datasheet entry; Section1

  • Heater Current 0.6

    450 mA

    Published in approved ECF80 target datasheet entry; Section1

  • Plate Supply Voltage 550

    550 V

    Published in approved ECF80 target datasheet entry; Section1

  • Plate Voltage 250

    250 V

    Published in approved ECF80 target datasheet entry; Section1

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

    550 V

    Published in approved ECF80 target datasheet entry; Section1

  • With cathode current of

    14 mA

    Published in approved ECF80 target datasheet entry; Section1

  • With cathode current of 14 mA

    175 V

    Published in approved ECF80 target datasheet entry; Section1

  • With cathode current less than

    10 mA

    Published in approved ECF80 target datasheet entry; Section1

  • With cathode current less than 10 mA

    200 V

    Published in approved ECF80 target datasheet entry; Section1

  • Cathode Current 14

    14 mA

    Published in approved ECF80 target datasheet entry; Section1

  • Plate Dissipation 1.5

    1.7 W

    Published in approved ECF80 target datasheet entry; Section1

  • With plate dissipation greater than

    1.2 W

    Published in approved ECF80 target datasheet entry; Section1

  • With plate dissipation greater than 1.2 watts

    0.5 W

    Published in approved ECF80 target datasheet entry; Section1

  • With p.late dissipation less than

    1.2 W

    Published in approved ECF80 target datasheet entry; Section1

  • Input Resistance at frequency of

    50 MHz

    Published in approved ECF80 target datasheet entry; Section1

  • Equivalent Noise Resistance

    1500 Ω

    Published in approved ECF80 target datasheet entry; Section1

  • For fixed-bias operation 0.5

    0.5 MΩ

    Published in approved ECF80 target datasheet entry; Section1

  • For cathode-bias operation 0.5

    1 MΩ

    Published in approved ECF80 target datasheet entry; Section1

  • Heater Voltage 6.3

    50 V

    Published in approved ECF80 target datasheet entry; Section1

  • Heater Current 0.78

    100 mA

    Published in approved ECF80 target datasheet entry; Section1

  • Plate Supply Voltage 550

    900 V

    Published in approved ECF80 target datasheet entry; Section1

  • Plate Voltage 300

    600 V

    Published in approved ECF80 target datasheet entry; Section1

  • Grid-No.2 Supply Voltage

    550 V

    Published in approved ECF80 target datasheet entry; Section1

  • Plate Dissipation 1

    7 W

    Published in approved ECF80 target datasheet entry; Section1

  • Grid-No.2 Input

    1.8 W

    Published in approved ECF80 target datasheet entry; Section1

  • Plate Voltage 100

    200 V

    Published in approved ECF80 target datasheet entry; Section1

  • For fixed-bias operation I

    1 MΩ

    Published in approved ECF80 target datasheet entry; Section1

  • For cathode-bias operation 2

    2 MΩ

    Published in approved ECF80 target datasheet entry; Section1

Characteristic

  • Plate Voltage 100

    170 V

    Published in approved ECF80 target datasheet entry; Section1

  • Transconductance 5000

    6200 µS

    Published in approved ECF80 target datasheet entry; Section1

  • Plate Current 14

    10 mA

    Published in approved ECF80 target datasheet entry; Section1

  • Plate Resistance (Approx.)

    0.02 MΩ

    Published in approved ECF80 target datasheet entry; Section1

  • Transconductance 2500

    6400 µS

    Published in approved ECF80 target datasheet entry; Section1

  • Plate Current 3.5

    35 mA

    Published in approved ECF80 target datasheet entry; Section1

  • Grid-No.2 Current

    7 mA

    Published in approved ECF80 target datasheet entry; Section1