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Voltage Pentode - Sharp Cutoff (single) ·Pentode

ACSP3

High-slope Mazda screened high-frequency pentode for fixed-gain RF amplification in AC mains receivers.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
M7A
Base pins
7
Nominal heater
4 V / 1 A

Description

High-slope screened HF pentode for A.C. mains receiver service.

Socket description

British/European 7-pin

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
M7A
Base pins
7
Nominal heater voltage
4 V
Nominal heater current
1 A
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
0.0075 S
Max plate voltage
250 V
Max screen voltage
250 V

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

1960 Mazda

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Typical anode current

    7.8 mA

    Screen80V

  • Typical anode current

    12.3 mA

    Screen200V

  • Typical screen current

    2.45 mA

    Screen80V

  • Typical screen current

    3.85 mA

    Screen200V

Characteristics

  • Plate resistance

    0.55 MOhm

    Screen80V

  • Plate resistance

    0.34 MOhm

    Screen200V

Capacitance

  • Input capacitance hot

    20 pF

    Screen80V