Alternatives & variations Download PDF datasheet

Voltage Radio Detector Converter ·Pentode-Triode

6X8

Combined triode-pentode for oscillator, mixer, frequency-converter, RF, or IF service in television, communications, or mobile receivers.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 2
Base: 9AK
Socket code: B9A
Base pins: 9
Nominal heater: 6.3 V / 450 mA

Description

Medium-mu triode plus sharp-cutoff pentode for television oscillator/mixer and amplifier 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: 9AK
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

9AK - Terminal pinout

Electrical assignments shared by every tube using this base designation.

Terminal	Section	Connection	Evidence
PIN11G3	A	G3 — Suppressor Grid EIA chart transcription, manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9AK
PIN22G1	B	G1 — Control Grid EIA chart transcription, manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9AK
PIN32P	B	P — Plate (Anode) EIA chart transcription, manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9AK
PIN4H	—	H — Heater EIA chart transcription, manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9AK
PIN5H	—	H — Heater EIA chart transcription, manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9AK
PIN6K	A	K — Cathode EIA chart transcription, manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9AK
PIN71G1	A	G1 — Control Grid EIA chart transcription, manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9AK
PIN81G2	A	G2 — Screen Grid EIA chart transcription, manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9AK
PIN91P	A	P — Plate (Anode) EIA chart transcription, manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9AK

Section ratings

2 physical sections, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances

Plate resistance: 750000 Ω
Transconductance: 0.0046 S
Max plate voltage: 250 V
Max screen voltage: 250 V
Max plate dissipation: 2 W
Max screen dissipation: 0.4 W
Max cathode current: 20 mA

Pentode section values mapped from converter-service maximum ratings and average characteristics.

Section 2

Triode

X-ray radiationInterelectrode capacitances

Plate resistance: 6900 Ω
Transconductance: 0.0058 S
Amplification factor: 40
Max plate voltage: 250 V
Max plate dissipation: 1.5 W
Max cathode current: 20 mA

Triode oscillator section values mapped from section-specific ratings and average characteristics.

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

195X General Electric Essential Characteristics

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

Plate voltage
250 V
ClassA
Screen-grid voltage
150 V
ClassA
Cathode resistor
200 ohm
ClassA
Plate current
7.7 mA
ClassA
Screen-grid current
1.6 mA
ClassA

Characteristic

Plate resistance
750000 ohm
ClassA
Transconductance
4600 uS
ClassA

SECTION 2

Triode

Other

Plate voltage
100 V
ClassA
Cathode resistor
100 ohm
ClassA
Plate current
8.5 mA
ClassA

Characteristic

Plate resistance
6900 ohm
ClassA
Transconductance
5800 uS
ClassA
Amplification factor
40
ClassA

Data set 02

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

Heater voltage
6.3 V
Nominal
Heater current
450 mA
Nominal
Plate voltage
125 V
ClassA
Screen voltage
125 V
ClassA
Grid 1 voltage
-1 V
ClassA

Characteristic

Plate current
9 mA
ClassA
Screen current
2.2 mA
ClassA
Transconductance
5500 uS
ClassA
Plate resistance
300000 ohm
ClassA
Zero-bias transconductance
5700 uS
ClassA

SECTION 2

Triode

Other

Heater voltage
6.3 V
Nominal
Heater current
450 mA
Nominal
Plate voltage
125 V
ClassA
Grid 1 voltage
-1 V
ClassA

Characteristic

Plate current
12 mA
ClassA
Transconductance
6500 uS
ClassA
Plate resistance
6000 ohm
ClassA
Amplification factor
40
ClassA

Data set 03

1965 Sylvania Electronic Tubes Vol3

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

GridToPlateCapacitanceMaximum
0.06 pF
Input Capacitance
4.5 pF
Output Capacitance
1.4 pF
Plate Resistance
750000 ohm
Transconductance
4000 uS
TriodeConnectedAmplificationFactor
42
TriodeConnectedPlateResistance
7900 ohm

Other

Plate Voltage
150 V
Mixer
Screen Voltage
150 V
Mixer
Cathode Bias Resistance
200 ohm
Mixer
Plate Current
7.7 mA
Mixer
Screen Current
1.6 mA
Mixer

SECTION 2

Triode

Characteristic

Heater Voltage
6.3 V
Heater Current
450 mA
Grid To Plate Capacitance
1.4 pF
Input Capacitance
2.6 pF
Output Capacitance
1 pF
Transconductance
4000 uS
Amplification Factor
40

Other

Plate Voltage
150 V
Oscillator
Plate Current
8.5 mA
Oscillator

Data set 04

1966 Tung Sol Electronic Tubes 2 of 4

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

Plate voltage
125 V
ClassA
Grid #2 voltage
125 V
ClassA
Grid #1 voltage
-1 V
ClassA
Plate current
9 mA
ClassA
Grid #2 current
2.2 mA
ClassA

Characteristic

Transconductance
5500 uS
Plate resistance
300000 ohm

Capacitance

Grid-to-plate capacitance
0.02 pF
Input capacitance
5 pF
Output capacitance
2.6 pF

SECTION 2

Triode

Other

Plate voltage
125 V
ClassA
Grid #1 voltage
-1 V
ClassA
Plate current
12 mA
ClassA

Characteristic

Transconductance
6500 uS
Plate resistance
6000 ohm
Amplification factor
40

Capacitance

Grid-to-plate capacitance
1.7 pF
Input capacitance
3 pF
Output capacitance
1.4 pF

Data set 05

1968 General Electric Co

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

Conversion Transconductance
2100 uS
Mixer;PentodeConnection

SECTION 2

Triode

Other

Oscillator Power Output
0.5 W
250MHz

Data set 06

1971 RCA HB3 Binder 5 of 7

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

Plate voltage
125 V
Pentode
Screen voltage
125 V
Pentode
Plate current
9 mA
Pentode
Screen current
2.2 mA
Pentode

Characteristic

Plate resistance
300000 ohm
Pentode
Transconductance
5500 uS
Pentode

Capacitance

Grid-to-plate capacitance
0.06 pF
Pentode

SECTION 2

Triode

Other

Heater voltage
6.3 V
Heater current
450 mA
Plate voltage
125 V
Triode
Plate current
12 mA
Triode

Characteristic

Plate resistance
6000 ohm
Triode
Transconductance
6500 uS
Triode
Amplification factor
40
Triode