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Voltage - Triode (single) ·Triode

4215A

Directly heated or receiving triode documented by the manufacturer; available source material does not establish a narrower functional category strongly enough for reassignment.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
SPECIALMINI4
Base pins
4
Nominal heater
1.1 V / 250 mA

Description

The 4215A is a triode described in the Standard Valves datasheet, using a directly heated filament cathode and published operating data.

Socket description

Special miniature 4-contact socket family

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
SPECIALMINI4
Base pins
4
Nominal heater voltage
1.1 V
Nominal heater current
250 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

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
25000 Ω
Transconductance
0.00023999999999999998 S
Amplification factor
6
Max plate voltage
100 V
Max cathode current
22 mA

Published ratings and characteristics promoted where directly established by the datasheet.

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

1937 Standard Valves

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Grid-anode capacitance

    35 pF

    Published datasheet value

  • Anode-filament capacitance

    1 pF

    Published datasheet value

  • Grid-filament capacitance

    20 pF

    Published datasheet value

Data set 02

1946 Standard Telephone and Cables

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Mutual conductance

    240 µS

    Published characteristic; normalized from mA/V

Other

  • Grid-anode capacity

    3.5 pF

    Published interelectrode capacitance

  • Anode-filament capacity

    5 pF

    Published interelectrode capacitance

  • Maximum direct anode current

    22 mA

    Maximum safe operating rating