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Power - Triode (over 1000V 100W) ·Triode

3J221E

Air-blast-cooled very-high-power RF triode for large transmitting equipment.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
22 V / 70 A

Description

Air-blast-cooled high-power RF triode.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
-
Nominal heater voltage
22 V
Nominal heater current
70 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

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
2900 Ω
Amplification factor
26
Max plate voltage
17500 V
Max plate dissipation
20000 W
Max cathode current
2.5 A

Values transcribed from the approved datasheet; additional published data 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

1946 Standard Telephone and Cables

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Grid to anode

    26 pF

    Published direct interelectrode capacitance

  • Grid to filament

    1.3 pF

    Published direct interelectrode capacitance

  • Anode to filament

    20 pF

    Published direct interelectrode capacitance

  • Heater/filament nominal current

    70 A

    Nominal published value

Data set 02

1947 Standard Valves

Published operating points and test conditions from this source.

SECTION 1

Triode

Capacitance

  • Grid-anode capacitance

    26 pF

  • Grid-cathode/filament capacitance

    1.3 pF

  • Anode-cathode/filament capacitance

    20 pF

Other

  • Maximum frequency for published rating

    22 MHz

  • Cooling method

    Air blast