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Voltage Pentode or Tetrode (under 100V) ·Tetrode

A241

Early directly heated Philips high-vacuum tetrode for battery receivers, designed for low-voltage detector and amplifier service with economical filament operation.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
Philips 4-pin
Socket code
-
Base pins
4
Nominal heater
1.85 V / 60 mA

Description

Philips A241 is an early directly heated high-vacuum tetrode for battery receivers. The Dutch datasheet specifies very low filament current, low-voltage operation, and use as detector and amplifier.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
Philips 4-pin
Socket code
-
Base pins
4
Nominal heater voltage
1.85 V
Nominal heater current
60 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

Philips 4-pin - 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

Tetrode

X-ray radiationInterelectrode capacitances
Plate resistance
4500 Ω
Transconductance
0.001 S
Amplification factor
4.5
Max plate voltage
20 V

Published ratings and characteristics promoted where semantically applicable; additional values retained as section 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

1999 Philips 0-D

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Characteristics

  • Filament voltage range

    1.7 to 2 V

    Published datasheet value

  • Filament current

    60 mA

    Published datasheet value

  • Saturation current

    10 mA

    Published datasheet value

  • Maximum quiescent current

    - to 4 mA

    Published datasheet value

  • Amplification factor

    4.5

    Published datasheet value

  • Maximum transconductance

    - to 1 mA/V

    Published datasheet value

  • Minimum internal resistance

    4500 to - Ω

    Published datasheet value

Other

  • Anode voltage range

    2 to 20 V

    Published datasheet value