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Power - Tetrode (NOT beam) (over 1000V 100W) ·Tetrode

4250A

Power transmitting tetrode for RF amplifier, oscillator, and modulator service, with 250 W plate dissipation and RF output reaching several hundred watts.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
GIANT5
Base pins
5
Nominal heater
5 V / 14.5 A

Description

4250A is a Tetrode device. Power transmitting tetrode; supplied table explicitly co-designates 4-250A/5D22.

Socket description

Giant 5-contact base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
GIANT5
Base pins
5
Nominal heater voltage
5 V
Nominal heater current
14.5 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

Tetrode

X-ray radiationInterelectrode capacitances
Transconductance
0.004 S
Amplification factor
5.1
Max plate voltage
4000 V
Max screen voltage
600 V
Max plate dissipation
250 W
Max screen dissipation
35 W
Max grid dissipation
10 W
Max cathode current
350 mA

Highest applicable published rating promoted; service-specific CW, RF, audio, industrial, and pulse limits retained as parameter rows.

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

1950 General Electric Transmitting Types

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Characteristic

  • Transconductance

    4000 µS

  • Amplification Factor

    5.1

Other

  • Maximum Plate Voltage

    4000 V

  • Maximum Plate Dissipation

    250 W

  • Maximum Cathode Current

    510 mA

  • Operating Frequency Maximum

    75 MHz

  • Maximum Signal Power Output

    1040 W

    AudioFrequency,ClassAB

Data set 02

1953 Amperex

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Other

  • Maximum frequency at full ratings

    75 MHz

  • Reduced-rating frequency

    120 MHz

  • Peak cathode current maximum

    2.6 A

Characteristics

  • Grid-plate capacitance maximum

    0.11 pF

Data set 03

1956 RCA Transmitting Tubes

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Other

  • Maximum signal power output

    1040 W

    ClassAB

Data set 04

1962 Eimac

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Characteristic

  • Frequency for Maximum Ratings

    110 MHz

Capacitance

  • Grid-Plate Capacitance

    0.12 pF

    Average

  • Input Capacitance

    12.7 pF

    Average

  • Output Capacitance

    4.5 pF

    Average

Data set 05

1963 Amperex Condensed

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Other

  • Plate current

    312 mA

    RFAmplifierOrOscillator

  • RF output power

    1000 W

    RFAmplifierOrOscillator

  • Grid voltage

    -225 V

    RFAmplifierOrOscillator

  • Grid current

    90 mA

    RFAmplifierOrOscillator

  • Screen voltage

    500 V

    RFAmplifierOrOscillator

Data set 06

1965 Eimac Tube Manual

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Characteristic

  • Heater/filament voltage

    5 V

  • Heater/filament current

    14.5 A

  • Amplification factor

    5.1

  • Transconductance

    4000 uS

Capacitance

  • Input/grid-cathode capacitance

    12.7 pF

  • Output/plate-cathode capacitance

    4.5 pF

  • Feedback/grid-plate capacitance

    0.12 pF

Other

  • Maximum plate voltage

    4000 V

  • Maximum screen voltage

    600 V

  • Maximum plate dissipation

    250 W

  • Maximum screen dissipation

    35 W

  • Maximum grid dissipation

    10 W

  • Maximum plate/cathode current

    350 mA

  • Frequency for maximum ratings

    110 MHz

  • Plate-modulated maximum plate voltage

    3200 V

    PlateModulated

  • Plate-modulated plate dissipation

    165 W

    PlateModulated

  • Typical RF plate voltage

    4000 V

    ClassC

Data set 07

1965 Penta Labs Power Tubes

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Characteristic

  • Heater/filament voltage

    5 V

  • Heater/filament current

    14.5 A

  • Amplification factor

    5.1

  • Transconductance

    4000 uS

Other

  • Maximum plate voltage

    4000 V

  • Maximum screen voltage

    600 V

  • Maximum plate dissipation

    250 W

  • Maximum control-grid dissipation

    10 W

  • Source language

    English

  • Maximum frequency for full ratings

    75 MHz

  • Plate-modulated maximum plate voltage

    3200 V

Capacitance

  • Grid-plate capacitance

    0.12 pF

  • Input capacitance

    12.7 pF

  • Output capacitance

    4.5 pF

Application

  • Primary application

    Power tetrode with 250 W plate dissipation for amplifier, oscillator, and modulator service.

Construction

  • Cooling

    Radiation/convection or source-specific

  • Electrode structure

    Tetrode