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

3CX3000F7

High-mu forced-air-cooled power triode with flexible grid and filament leads, intended principally for grounded-grid RF amplification. It combines multi-kilowatt dissipation with high power gain and substantial RF output.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
7.5 V / 50.5 A

Description

High-mu forced-air ceramic-metal power triode with flexible grid/filament leads.

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
7.5 V
Nominal heater current
50.5 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

Triode

X-ray radiationInterelectrode capacitances
Amplification factor
160
Max plate voltage
5000 V
Max plate dissipation
4000 W
Max grid dissipation
225 W
Max cathode current
2.5 A

Promoted ratings mapped semantically from printed characteristics/maximum-ratings tables; remaining published electrical and operating-condition data retained densely 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

1965 Eimac Tube Manual

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Grounded-Filament Input Capacitance

    38 pF

  • Grounded-Filament Output Capacitance

    0.6 pF

  • Grounded-Filament Grid-Plate Capacitance

    24 pF

  • Grounded-Grid Input Capacitance

    38 pF

  • Grounded-Grid Output Capacitance

    24 pF

  • Grounded-Grid Plate-Cathode Capacitance

    0.6 pF

  • Frequency Maximum

    30 MHz

  • RF Plate Voltage Maximum

    5000 V

  • RF Plate Current Maximum

    2.5 A

  • Typical Power Gain Minimum

    20 ratio

  • Forced-Air Cooling Required

    1 boolean

Data set 02

1975 Eimac Tube Manual

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Grounded-Filament Input Capacitance

    38 pF

  • Grounded-Filament Output Capacitance

    0.6 pF

  • Grounded-Filament Grid-Plate Capacitance

    24 pF

  • Grounded-Grid Input Capacitance

    38 pF

  • Grounded-Grid Output Capacitance

    24 pF

  • Grounded-Grid Plate-Cathode Capacitance

    0.6 pF

  • Frequency Maximum

    30 MHz

  • RF Plate Voltage Maximum

    5000 V

  • RF Plate Current Maximum

    2.5 A

Characteristic

  • Typical Power Gain Minimum

    20 ratio

    GroundedGrid

Data set 03

1976 Eimac Tube Manual

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Grounded-Filament Input Capacitance

    38 pF

  • Grounded-Filament Output Capacitance

    0.6 pF

  • Grounded-Filament Grid-Plate Capacitance

    24 pF

  • Grounded-Grid Input Capacitance

    38 pF

  • Grounded-Grid Output Capacitance

    24 pF

  • Grounded-Grid Plate-Cathode Capacitance

    0.6 pF

  • Frequency Maximum

    30 MHz

  • RF Plate Voltage Maximum

    5000 V

  • RF Plate Current Maximum

    2.5 A

Characteristic

  • Typical Power Gain Minimum

    20 ratio

    GroundedGrid

Data set 04

199X Svetlana

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Current @

    7.5 V

    amplifiers. A modern mesh filament is used,

  • Input

    38 pF

    amplifiers. A modern mesh filament is used,

  • Output

    24 pF

    amplifiers. A modern mesh filament is used,

  • Feedback

    0.6 pF

    amplifiers. A modern mesh filament is used,

  • Input

    38 pF

    amplifiers. A modern mesh filament is used,

  • Output

    0.6 pF

    amplifiers. A modern mesh filament is used,

  • Feedback

    24 pF

    amplifiers. A modern mesh filament is used,

  • Maximum frequency for full ratings (CW)

    75 MHz

    amplifiers. A modern mesh filament is used,

Other

  • DC plate voltage

    5000 V

    Maximum Ratings

  • DC plate current

    2.5 A

    Maximum Ratings

  • Plate dissipation

    4000 W

    Maximum Ratings

  • Grid dissipation

    225 W

    Maximum Ratings

  • (Frequencies to

    30 MHz

    Typical Operation

  • Plate Voltage 4000 4800

    4800 V

    Typical Operation

  • Zero-signal plate current* 0.25 0.35

    350 mA

    Typical Operation

  • Single-tone plate current 2.00 1.68

    2 A

    Typical Operation

  • Grid bias 0 0

    0 V

    Typical Operation

  • Single-tone grid current* 0.61 0.46

    600 mA

    Typical Operation

  • Peak driving power 420 293

    410 W

    Typical Operation

  • Plate dissipation 2285 2275

    2775 W

    Typical Operation

  • Single-tone plate output power 6030 6000

    7266 W

    Typical Operation

  • Resonant load impedance 1210 1720

    1425 Ohms

    Typical Operation

  • Driving impedance 47.5 50.0

    46.3 Ohms

    Typical Operation

  • DC Plate voltage

    5000 V

    Maximum Ratings

  • DC Plate current

    2.5 A

    Maximum Ratings

  • Plate dissipation

    4000 W

    Maximum Ratings

  • Grid dissipation

    225 W

    Maximum Ratings

  • (Frequencies to

    110 MHz

    Typical operation

  • Plate voltage 3500

    4800 V

    Typical operation

  • Grid voltage -50

    -60 V

    Typical operation

  • Plate current 1.30

    1.54 A

    Typical operation

  • Grid current* 0.42

    480 mA

    Typical operation

  • Peak RF cathode voltage* 220

    267 V

    Typical operation

  • Calculated driving power* 310

    435 W

    Typical operation

  • Plate dissipation 985

    1480 W

    Typical operation

  • Useful output power 3300

    5500 W

    Typical operation

  • DC plate voltage

    5000 V

    Maximum Ratings (per tube)

  • DC plate current

    2.5 A

    Maximum Ratings (per tube)

  • Plate dissipation

    4000 W

    Maximum Ratings (per tube)

  • Grid dissipation

    225 W

    Maximum Ratings (per tube)

  • Plate voltage

    4000 V

    Typical Operation (two tubes, sinusoidal waveform)

  • Zero-signal plate current

    500 mA

    Typical Operation (two tubes, sinusoidal waveform)

  • Maximum-signal plate current

    3.58 A

    Typical Operation (two tubes, sinusoidal waveform)

  • Maximum-signal grid current

    580 mA

    Typical Operation (two tubes, sinusoidal waveform)

  • Peak AF grid voltage

    190 V

    Typical Operation (two tubes, sinusoidal waveform)

  • Peak driving power

    115 W

    Typical Operation (two tubes, sinusoidal waveform)

  • Maximum-signal plate dissipation

    1850 W

    Typical Operation (two tubes, sinusoidal waveform)

  • Plate output power

    10500 W

    Typical Operation (two tubes, sinusoidal waveform)

  • Load resistance (plate-to-plate)

    2720 Ohms

    Typical Operation (two tubes, sinusoidal waveform)

  • Filament current at

    7.5 V

    Typical Operation (two tubes, sinusoidal waveform)

  • Input 30.0

    45 pF

    Typical Operation (two tubes, sinusoidal waveform)

  • Output 20.0

    28 pF

    Typical Operation (two tubes, sinusoidal waveform)

  • Feedback —

    1 pF

    Typical Operation (two tubes, sinusoidal waveform)

  • Input 30.0

    45 pF

    Typical Operation (two tubes, sinusoidal waveform)

  • Output

    1 pF

    Typical Operation (two tubes, sinusoidal waveform)

  • Feedback 20.0

    28 pF

    Typical Operation (two tubes, sinusoidal waveform)

  • Zero-Bias plate current (Eb =

    5000 V

    Typical Operation (two tubes, sinusoidal waveform)

  • Cut-off bias (Eb =

    5000 V

    Typical Operation (two tubes, sinusoidal waveform)

  • below

    250 ˚C

    Typical Operation (two tubes, sinusoidal waveform)

  • maintain these temperatures below

    225 ˚C

    Typical Operation (two tubes, sinusoidal waveform)

  • with an inlet-air temperature of

    40 ˚C

    Typical Operation (two tubes, sinusoidal waveform)

  • tabulated. At frequencies above

    30 MHz

    Typical Operation (two tubes, sinusoidal waveform)