8KR8

Triode/pentode television signal processor with a 20 mS video pentode and triode for sync or sound-IF service.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 2
Base: -
Socket code: B9A
Base pins: 9
Nominal heater: 8 V / 600 mA

Description

Medium-mu triode plus sharp-cutoff pentode; the pentode is a high-transconductance video amplifier and the triode is for general voltage-amplifier, sync-separator, or sound-IF 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: -
Socket code: B9A
Base pins: 9
Nominal heater voltage: 8 V
Nominal heater current: 600 mA
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

2 physical sections, each with unique specifications.

Section 1

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

Published maximum ratings and characteristics promoted semantically from the approved source.

Section 2

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: 1.1 W

Published maximum ratings and characteristics promoted semantically from the approved source.

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

1950 Sylvania

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

Plate Resistance
4400 ohm
Transconductance
10400 µS
Amplification Factor
46

Other

Maximum Plate Voltage
330 V
Maximum Plate Dissipation
2 W
Plate Voltage
125 V
Triode section
Plate Current
15 mA
Triode section

SECTION 2

Pentode

Characteristic

Plate Resistance
60000 ohm
Transconductance
20000 µS

Other

Maximum Plate Voltage
330 V
Maximum Screen Voltage
330 V
Maximum Plate Dissipation
5 W
Maximum Screen Dissipation
1.1 W
Plate Voltage
200 V
Pentode section
Screen Voltage
100 V
Pentode section
Plate Current
19.5 mA
Pentode section