6KR8A

Triode-pentode combination for television receiver signal-amplifier service.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 2
Base: 9DX
Socket code: B9A
Base pins: 9
Nominal heater: 6.3 V / 750 mA

Description

Miniature medium-mu triode and sharp-cutoff pentode for video-amplifier and general-purpose 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: 9DX
Socket code: B9A
Base pins: 9
Nominal heater voltage: 6.3 V
Nominal heater current: 750 mA
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

9DX - Terminal pinout

Electrical assignments shared by every tube using this base designation.

Terminal	Section	Connection	Evidence
PIN12K	B	K — Cathode EIA transcription; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9DX
PIN22G1	B	G1 — Control Grid EIA transcription; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9DX
PIN32P	B	P — Plate (Anode) EIA transcription; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9DX
PIN4H	—	H — Heater EIA transcription; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9DX
PIN5H	—	H — Heater EIA transcription; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9DX
PIN61G3	A	G3 — Suppressor GridGroup 9DX6 EIA transcription; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9DX
PIN6IS	A	IS — Internal ScreenGroup 9DX6 EIA transcription; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9DX
PIN61K	A	K — CathodeGroup 9DX6 EIA transcription; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9DX
PIN71G1	A	G1 — Control Grid EIA transcription; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9DX
PIN81G2	A	G2 — Screen Grid EIA transcription; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9DX
PIN91P	A	P — Plate (Anode) EIA transcription; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 131, 9DX

Section ratings

2 physical sections, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances

Plate resistance: 60000 Ω
Transconductance: 0.02 S
Max plate voltage: 330 V
Max screen voltage: 330 V
Max plate dissipation: 5 W
Max screen dissipation: 1.5 W

Section 2

Triode

X-ray radiationInterelectrode capacitances

Plate resistance: 4400 Ω
Transconductance: 0.0104 S
Amplification factor: 46
Max plate voltage: 330 V
Max plate dissipation: 2 W

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

1968 General Electric Co

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

Maximum Plate Voltage
330 V
Maximum Screen Supply Voltage
330 V
Maximum Plate Dissipation
5 W
Maximum Screen Dissipation
1.5 W

Characteristic

Plate Resistance
60000 ohm
PlateVoltage=200V
Transconductance
20000 uS
PlateVoltage=200V

Capacitance

Grid1 To Plate Capacitance
0.075 pF
Section1
Input Capacitance
13 pF
Section1
Output Capacitance
5.5 pF
Section1

SECTION 2

Triode

Other

Maximum Plate Voltage
330 V
Maximum Plate Dissipation
2 W

Characteristic

Amplification Factor
46
Plate Resistance
4400 ohm
Transconductance
10400 uS

Capacitance

Grid To Plate Capacitance
2.6 pF
Section2
Input Capacitance
4.2 pF
Section2
Output Capacitance
3 pF
Section2