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Power - Pentode Single (NOT beam) (under 10W) ·Pentode

N309

High-transconductance Marconi pentode designed specifically for television video-output amplification.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B9A
Base pins
9
Nominal heater
15 V / 300 mA

Description

The Marconi N309 is a high-transconductance video power pentode for television video-output 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
15 V
Nominal heater current
300 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

1 physical section, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances
Transconductance
0.009 S
Max plate voltage
250 V
Max screen voltage
250 V
Max plate dissipation
9 W
Max screen 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

1955 Marconi

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Heater voltage

    15 V

  • Heater current

    300 mA

  • Maximum plate voltage

    250 V

  • Maximum screen voltage

    250 V

  • Maximum plate dissipation

    9 W

  • Maximum screen dissipation

    2 W

Characteristic

  • Transconductance

    9000 uS

Application

  • Primary application

    High-transconductance video power pentode for television video-output service.