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

4CX250B

High-power ceramic/metal transmitting tetrode designed for RF power amplification, linear amplification, oscillation, modulation, broadcast, or related high-power service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
RADIALRING9
Base pins
9
Nominal heater
6 V / 2.6 A

Description

All-ceramic external-anode tetrode for airborne/mobile UHF, single-sideband, and pulse applications.

Socket description

9-contact radial-ring transmitting-tube base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
RADIALRING9
Base pins
9
Nominal heater voltage
6 V
Nominal heater current
2.6 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
Amplification factor
5
Max plate voltage
2000 V
Max screen voltage
400 V
Max plate dissipation
250 W
Max screen dissipation
12 W
Max grid dissipation
2 W
Max cathode current
250 mA

Promoted fields populated from published ratings/characteristics; additional published values retained in TUBE_SECTION_PARAMETER.

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

1940 RCA

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Characteristics

  • Heater or filament voltage

    6 V

    Published nominal value

  • Heater or filament current

    2.6 A

    Published nominal/aggregate value

Other

  • Maximum plate dissipation

    250 W

    Published maximum rating

  • Useful RF power output

    250 W

    Class-C service

  • Maximum frequency

    500 MHz

    Published

Data set 02

1962 Eimac

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Capacitance

  • Input Capacitance

    15.7 pF

  • Output Capacitance

    4.5 pF

  • Grounded Cathode Feedback Capacitance

    0.04 pF

  • Grounded Grid Feedback Capacitance

    0.01 pF

Other

  • Frequency of Maximum Rating CW

    500 MHz

  • Maximum DC Plate Current

    250 mA

  • Typical Linear Plate Voltage

    2000 V

    ClassAB1

  • Typical Linear Plate Output Power

    300 W

    ClassAB1

Data set 03

1963 Amperex Condensed

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Other

  • Plate voltage

    2000 V

    RFPowerAmplifier

  • Plate current

    250 mA

    RFPowerAmplifier

  • Power output

    390 W

    RFPowerAmplifier

  • Control-grid voltage

    -90 V

    RFPowerAmplifier

  • Grid current

    26 mA

    RFPowerAmplifier

  • Screen voltage

    250 V

    RFPowerAmplifier

  • Maximum frequency at full input

    500 MHz

    RFPowerAmplifier

Capacitance

  • Grid-to-plate capacitance

    0.06 pF

    Section1

  • Input capacitance

    15.7 pF

    Section1

  • Output capacitance

    4.5 pF

    Section1

Data set 04

1971 RCA HB3 Binder 6 of 7

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Other

  • Maximum DC Plate Voltage

    2000 V

    Forced-air-cooled RF service Alias of 7203.

  • Maximum DC Screen Voltage

    400 V

    Forced-air-cooled RF service Alias of 7203.

  • Plate Dissipation

    250 W

    Forced-air-cooled RF service Alias of 7203.

  • Screen Input

    12 W

    Forced-air-cooled RF service Alias of 7203.

  • Typical DC Plate Voltage

    2000 V

    Forced-air-cooled RF service Alias of 7203.

  • Typical DC Screen Voltage

    350 V

    Forced-air-cooled RF service Alias of 7203.

  • Useful Power Output

    225 W

    Forced-air-cooled RF service Alias of 7203.

Characteristics

  • Mu Factor, Screen to Control Grid

    5

    Forced-air-cooled RF service Alias of 7203.

  • Grid-No.1 to Plate Capacitance

    0.03 pF

    Forced-air-cooled RF service Alias of 7203.

  • Grid-No.1 to Cathode/Screen/Heater Capacitance

    16 pF

    Forced-air-cooled RF service Alias of 7203.

  • Plate to Cathode/Screen/Heater Capacitance

    4.4 pF

    Forced-air-cooled RF service Alias of 7203.