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7AD7

Pentode documented with Class A ratings and operating characteristics. Available manufacturer and handbook material establishes signal-amplifier service without sufficiently explicit application or cutoff terminology for a more specialized functional type.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: 8V
Socket code: LOCTAL8
Base pins: 8
Nominal heater: 6.3 V / 600 mA

Description

The 7AD7 is a Pentode vacuum tube as described by the source datasheet.

Socket description

Loctal 8-contact base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: 8V
Socket code: LOCTAL8
Base pins: 8
Nominal heater voltage: 6.3 V
Nominal heater current: 600 mA
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

8V - Terminal pinout

Electrical assignments shared by every tube using this base designation.

Terminal	Section	Connection	Evidence
PIN1H	—	H — Heater EIA source transcription; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 129, 8V
PIN2P	A	P — Plate (Anode) EIA source transcription; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 129, 8V
PIN3G2	A	G2 — Screen Grid EIA source transcription; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 129, 8V
PIN4G3	A	G3 — Suppressor Grid EIA source transcription; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 129, 8V
PIN5IS	A	IS — Internal Screen EIA chart transcription; manufacturer verification pending	Unverified EIA Base Connections, printed page 129, 8V
PIN6G1	A	G1 — Control Grid EIA chart transcription; manufacturer verification pending	Unverified EIA Base Connections, printed page 129, 8V
PIN7K	A	K — Cathode EIA chart transcription; manufacturer verification pending	Unverified EIA Base Connections, printed page 129, 8V
PIN8H	—	H — Heater EIA chart transcription; manufacturer verification pending	Unverified EIA Base Connections, printed page 129, 8V

Section ratings

1 physical section, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances

Plate resistance: 300000 Ω
Transconductance: 0.0095 S
Max plate voltage: 300 V
Max screen voltage: 300 V
Max plate dissipation: 10 W
Max screen dissipation: 1.2 W

Published handbook 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
300 V
Published handbook rating
Maximum screen voltage
150 V
Published handbook rating
Plate voltage
250 V
ClassA
Screen voltage
150 V
ClassA
Plate current
28 mA
ClassA
Screen current
7 mA
ClassA

Characteristic

Plate resistance
300000 ohm
Published handbook characteristic
Transconductance
9500 µS
Published handbook characteristic
Heater voltage
6.3 V
Published heater rating
Heater current
600 mA
Published heater rating

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
600 mA
Nominal
Plate voltage
300 V
Typical operating conditions
Screen voltage
300 V
Typical operating conditions
Plate current
28 mA
Typical operating conditions
Screen current
7 mA
Typical operating conditions