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Power - Pentode (NOT beam) ·Pentode

9BM5

300 mA series-heater audio power pentode, co-designated with 9P9, for transformerless receiver output stages.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
7BZ
Socket code
B7G
Base pins
7
Nominal heater
9.5 V / 300 mA

Description

Printed co-designation for the 9P9 300 mA series-heater audio output pentode.

Socket description

Miniature 7-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
7BZ
Socket code
B7G
Base pins
7
Nominal heater voltage
9.5 V
Nominal heater current
300 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

7BZ - Terminal pinout

Electrical assignments shared by every tube using this base designation.

TerminalSectionConnectionEvidence
PIN1Pin 1AG1 — Control GridVerified

Tung-Sol 6AQ5/6AQ5A 7BZ basing; manufacturer pinout

PIN2Pin 2AG3 — Suppressor GridGroup BZ2Verified

Tung-Sol 6AQ5/6AQ5A 7BZ basing; manufacturer pinout

PIN2Pin 2AK — CathodeGroup BZ2Verified

Tung-Sol 6AQ5/6AQ5A 7BZ basing; manufacturer pinout

PIN3Pin 3—H — HeaterVerified

Tung-Sol 6AQ5/6AQ5A 7BZ basing; manufacturer pinout

PIN4Pin 4—H — HeaterVerified

Tung-Sol 6AQ5/6AQ5A 7BZ basing; manufacturer pinout

PIN5Pin 5AP — Plate (Anode)Verified

Tung-Sol 6AQ5/6AQ5A 7BZ basing; manufacturer pinout

PIN6Pin 6AG2 — Screen GridVerified

Tung-Sol 6AQ5/6AQ5A 7BZ basing; manufacturer pinout

PIN7Pin 7AG1 — Control GridVerified

Tung-Sol 6AQ5/6AQ5A 7BZ basing; manufacturer pinout

Section ratings

1 physical section, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
60000 Ω
Transconductance
0.007 S
Max plate voltage
250 V
Max screen voltage
250 V

Published maximum ratings and representative operating characteristics reviewed.

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

  • Maximum plate voltage

    250 V

    Published handbook rating

  • Maximum screen voltage

    250 V

    Published handbook rating

  • Plate voltage

    250 V

    ClassA

  • Screen voltage

    250 V

    ClassA

  • Control-grid bias

    6 V

    ClassA

  • Plate current

    30 mA

    ClassA

  • Screen current

    3 mA

    ClassA

  • Load resistance

    7000 ohm

    ClassA

  • Power output

    3.5 W

    ClassA

Characteristic

  • Plate resistance

    60000 ohm

    Published handbook characteristic

  • Transconductance

    7000 µS

    Published handbook characteristic

  • Heater/filament voltage

    9.5 V

    Published heater/filament rating

  • Heater/filament current

    300 mA

    Published heater/filament rating

Data set 02

1968 Mazda Belvu

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristics

  • Heater or filament voltage

    9.5 V

    Published nominal value

  • Heater or filament current

    300 mA

    Published nominal value