AP4

Acorn pentode for RF amplifier and detector service. Compact low-capacitance construction minimizes lead lengths for improved high-frequency performance while providing useful small-signal gain.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: -
Socket code: ACORN7
Base pins: 7
Nominal heater: 4 V / 200 mA

Description

Acorn pentode for RF amplifier and detector service.

Socket description

Acorn radial 7-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: -
Socket code: ACORN7
Base pins: 7
Nominal heater voltage: 4 V
Nominal heater current: 200 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

Plate resistance: 3500000 Ω
Transconductance: 0.0014 S
Max plate voltage: 250 V
Max screen voltage: 100 V
Max plate dissipation: 0.8 W
Max screen dissipation: 0.15 W

Published Mullard ratings, characteristics, capacitances, and operating data promoted where applicable; additional electrical values retained as parameters.

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

1963 Mullard

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

Plate voltage operating
250 V
Screen voltage operating
100 V
Plate current
2 mA
Screen current
0.7 mA
Control-grid voltage
-3 V

Characteristics

Transconductance
1.4 mA/V
Amplification grid1-to-grid2
5000

Application

Application
RF amplifier / anode detector