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Power - TV Vertical Output ·Pentode-Triode

6BM8

High-mu triode/power-pentode combination for compact audio amplification and television vertical-output circuitry.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 2
Base: 9EX
Socket code: B9A
Base pins: 9
Nominal heater: 6.3 V / 780 mA

Description

High-mu triode plus power pentode used in television vertical circuits and as an audio-frequency output tube.

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: 9EX
Socket code: B9A
Base pins: 9
Nominal heater voltage: 6.3 V
Nominal heater current: 780 mA
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

9EX - Terminal pinout

Electrical assignments shared by every tube using this base designation.

Terminal	Section	Connection	Evidence
PIN1Base Pin	B	G1 — Control Grid Original chart label: 2G1; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EX
PIN2Base Pin	A	G3 — Suppressor GridGroup 9EX2 Original chart label: 1G3; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EX
PIN2Base Pin	A	K — CathodeGroup 9EX2 Original chart label: 1K; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EX
PIN3Base Pin	A	G1 — Control Grid Original chart label: 1G1; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EX
PIN4Base Pin	—	H — Heater Original chart label: H; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EX
PIN5Base Pin	—	H — Heater Original chart label: H; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EX
PIN6Base Pin	A	P — Plate (Anode) Original chart label: 1P; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EX
PIN7Base Pin	A	G2 — Screen Grid Original chart label: 1G2; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EX
PIN8Base Pin	B	K — Cathode Original chart label: 2K; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EX
PIN9Base Pin	B	P — Plate (Anode) Original chart label: 2P; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EX

Section ratings

2 physical sections, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances

Plate resistance: 20000 Ω
Transconductance: 0.0025 S
Amplification factor: 70
Max plate voltage: 300 V
Max plate dissipation: 1 W

Fixed ratings unavailable because the supplied source explicitly identifies missing pages.

Section 2

Pentode

X-ray radiationInterelectrode capacitances

Transconductance: 0.0064 S
Max plate voltage: 600 V
Max screen voltage: 300 V
Max plate dissipation: 7 W
Max screen dissipation: 1.8 W
Max cathode current: 50 mA

Fixed ratings unavailable because the supplied source explicitly identifies missing pages; surviving pages show pentode curves and audio-output application.

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 2

Pentode

Characteristic

PeakAnodeCurrentDesignPoint
80 mA
VerticalOutput;PlateVoltage=50V;ScreenVoltage=170V

Other

AudioOutputApplication
Transformerless audio output
Surviving circuit page

Data set 02

1963 Amperex Condensed

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

Heater voltage
6.3 V
Published heater rating
Heater current
780 mA
Published heater rating
Triode amplification factor
70
TriodeSection VoltageAmplifier
Triode plate resistance
28000 ohm
TriodeSection VoltageAmplifier

Other

Triode plate voltage
100 V
TriodeSection VoltageAmplifier
Triode grid voltage
0 V
TriodeSection VoltageAmplifier
Triode plate current
3.5 mA
TriodeSection VoltageAmplifier

SECTION 2

Pentode

Other

Pentode plate voltage
170 V
PentodeSection PowerOutput
Pentode screen voltage
115 V
PentodeSection PowerOutput
Pentode plate current
41 mA
PentodeSection PowerOutput
Pentode screen current
9 mA
PentodeSection PowerOutput
Pentode power output
7.5 W
PentodeSection PowerOutput

Characteristic

Pentode transconductance
7200 µS
PentodeSection PowerOutput

Data set 03

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
0.6 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Current at heater volts = 6.3 — published value 1
6.3 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Current at heater volts = 6.3 — published value 2
0.78 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Peak heater-cathode voltage
100 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid to plate
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 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.
Pin 9 —Triode Plate
9
Published datasheet value; multiple values represent separate source-table limits or conditions.
Plate Voltage — published value 1
100 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Plate Voltage — published value 2
200 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid-No.2 Voltage
200 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid-No.l Voltage — published value 1
0 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid-No.l Voltage — published value 2
-16 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid-No.1 Voltage (RMS)
6.6 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Plate Resistance (Approx.)
20000 ohm
Published datasheet value; multiple values represent separate source-table limits or conditions.
Transconductance — published value 1
2500
Published datasheet value; multiple values represent separate source-table limits or conditions.
Transconductance — published value 2
6400
Published datasheet value; multiple values represent separate source-table limits or conditions.
Plate Current — published value 1
3.5 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Plate Current — published value 2
35 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Signal Grid-No.2 Current
7 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Load Resistance
5600 ohm
Published datasheet value; multiple values represent separate source-table limits or conditions.
Plate Supply Voltage — published value 1
550 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Plate Supply Voltage — published value 2
900 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Plate Voltage — published value 1
300 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Plate Voltage — published value 2
600 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid-No.2 Supply Voltage
550 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid-No.2 Voltage
300 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid-No.2 Input
1.8 W
Published datasheet value; multiple values represent separate source-table limits or conditions.
Plate Dissipation
1 W
Published datasheet value; multiple values represent separate source-table limits or conditions.
Average Cathode Current — published value 1
15 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Average Cathode Current — published value 2
50 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
For fixed-bias operation — published value 1
1 ohm
Published datasheet value; multiple values represent separate source-table limits or conditions.
For fixed-bias operation — published value 2
1 ohm
Published datasheet value; multiple values represent separate source-table limits or conditions.
For cathode-bias operation — published value 1
2 ohm
Published datasheet value; multiple values represent separate source-table limits or conditions.
For cathode-bias operation — published value 2
2 ohm
Published datasheet value; multiple values represent separate source-table limits or conditions.
Between heater and cathode — published value 1
0.02 ohm
Published datasheet value; multiple values represent separate source-table limits or conditions.
Between heater and cathode — published value 2
0.02 ohm
Published datasheet value; multiple values represent separate source-table limits or conditions.

Other

Grid to heater
0.1 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid No.l to plate
0.3 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid-No.l to heater
0.3 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Max.-Signal Power Output
3.5 W
Published datasheet value; multiple values represent separate source-table limits or conditions.
At pl ate voltage less th an 250 volt s, maxi mum pl ate dissipation is7 watt s
250 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
at pl ate vo1 tage greater to an 250 volts, maximum plate d i ssip at ion i s 5 watts — published value 1
250 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
at pl ate vo1 tage greater to an 250 volts, maximum plate d i ssip at ion i s 5 watts — published value 2
5 V
Published datasheet value; multiple values represent separate source-table limits or conditions.

SECTION 2

Pentode

Other

Triode plate to pentode grid No 1 — published value 1
1 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Triode plate to pentode grid No 1 — published value 2
0.02 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Triode grid to pentode plate
0.02 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Triode grid to pentode grid No.1
0.025 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Triode plate to pentode plate
0.25 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.

Characteristics

Pin 3 —Pentode Grid No.1
3
Published datasheet value; multiple values represent separate source-table limits or conditions.
Pin 6 —Pentode Plate
6
Published datasheet value; multiple values represent separate source-table limits or conditions.

Data set 04

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

Input Resistance at frequency of
50 MHz
Published in approved ECL82 target datasheet entry; Section1
Equivalent Noise Resistance
1500 Ω
Published in approved ECL82 target datasheet entry; Section1
For fixed-bias operation 0.5
0.5 MΩ
Published in approved ECL82 target datasheet entry; Section1
For cathode-bias operation 0.5
1 MΩ
Published in approved ECL82 target datasheet entry; Section1
Heater Voltage 6.3
50 V
Published in approved ECL82 target datasheet entry; Section1
Heater Current 0.78
100 mA
Published in approved ECL82 target datasheet entry; Section1
Plate Supply Voltage 550
900 V
Published in approved ECL82 target datasheet entry; Section1
Plate Voltage 300
600 V
Published in approved ECL82 target datasheet entry; Section1
Grid-No.2 Supply Voltage
550 V
Published in approved ECL82 target datasheet entry; Section1
Plate Dissipation 1
7 W
Published in approved ECL82 target datasheet entry; Section1
Grid-No.2 Input
1.8 W
Published in approved ECL82 target datasheet entry; Section1
Plate Voltage 100
200 V
Published in approved ECL82 target datasheet entry; Section1
For fixed-bias operation I
1 MΩ
Published in approved ECL82 target datasheet entry; Section1
For cathode-bias operation 2
2 MΩ
Published in approved ECL82 target datasheet entry; Section1

Characteristic

Plate Resistance (Approx.)
0.02 MΩ
Published in approved ECL82 target datasheet entry; Section1
Transconductance 2500
6400 µS
Published in approved ECL82 target datasheet entry; Section1
Plate Current 3.5
35 mA
Published in approved ECL82 target datasheet entry; Section1
Grid-No.2 Current
7 mA
Published in approved ECL82 target datasheet entry; Section1

SECTION 2

Pentode

Other

Input Resistance at frequency of
50 MHz
Published in approved ECL82 target datasheet entry; Section2
Equivalent Noise Resistance
1500 Ω
Published in approved ECL82 target datasheet entry; Section2
For fixed-bias operation 0.5
0.5 MΩ
Published in approved ECL82 target datasheet entry; Section2
For cathode-bias operation 0.5
1 MΩ
Published in approved ECL82 target datasheet entry; Section2
Heater Voltage 6.3
50 V
Published in approved ECL82 target datasheet entry; Section2
Heater Current 0.78
100 mA
Published in approved ECL82 target datasheet entry; Section2
Plate Supply Voltage 550
900 V
Published in approved ECL82 target datasheet entry; Section2
Plate Voltage 300
600 V
Published in approved ECL82 target datasheet entry; Section2
Grid-No.2 Supply Voltage
550 V
Published in approved ECL82 target datasheet entry; Section2
Plate Dissipation 1
7 W
Published in approved ECL82 target datasheet entry; Section2
Grid-No.2 Input
1.8 W
Published in approved ECL82 target datasheet entry; Section2
Plate Voltage 100
200 V
Published in approved ECL82 target datasheet entry; Section2
For fixed-bias operation I
1 MΩ
Published in approved ECL82 target datasheet entry; Section2
For cathode-bias operation 2
2 MΩ
Published in approved ECL82 target datasheet entry; Section2

Characteristic

Plate Resistance (Approx.)
0.02 MΩ
Published in approved ECL82 target datasheet entry; Section2
Transconductance 2500
6400 µS
Published in approved ECL82 target datasheet entry; Section2
Plate Current 3.5
35 mA
Published in approved ECL82 target datasheet entry; Section2
Grid-No.2 Current
7 mA
Published in approved ECL82 target datasheet entry; Section2

Data set 05

199X Svetlana

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

HeaterVoltageNominal
6.3 V
Nominal
HeaterCurrentNominal
780 mA
Nominal
Maximum Plate Voltage
300 V
Maximum Plate Dissipation
1 W

SECTION 2

Pentode

Other

HeaterVoltageNominal
6.3 V
Nominal
HeaterCurrentNominal
780 mA
Nominal
Maximum Plate Voltage
600 V
Maximum Screen Voltage
300 V
Maximum Plate Dissipation
7 W