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Voltage Pentode - Remote Cutoff (single) ·Pentode

5661

Reliable voltage-amplifier pentode similar to the 12SK7, designed for severe vibration and intermittent service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
IO
Base pins
8
Nominal heater
12.6 V / 150 mA

Description

The 5661 is a voltage-amplifier pentode similar to the 12SK7 and designed for reliable performance under severe vibration and intermittent operation.

Socket description

International Octal

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
IO
Base pins
8
Nominal heater voltage
12.6 V
Nominal heater current
150 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
800000 Ω
Transconductance
0.002 S
Max plate voltage
300 V
Max screen voltage
125 V
Max plate dissipation
4 W
Max screen dissipation
0.4 W

250-V Class-A characteristic column promoted.

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

1968 General Electric Co

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate Voltage

    250 V

    ClassA

  • Screen Voltage

    100 V

    ClassA

Characteristic

  • Plate Current

    9.2 mA

    ClassA

  • Screen Current

    2.6 mA

    ClassA