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

3CX2500A3

All-ceramic-and-metal medium-mu transmitting triode for RF amplification, oscillation, and modulation. It offers about 2.5 kW plate dissipation and carries full ratings into the VHF region for professional transmitter service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
7.5 V / 51 A

Description

All-ceramic-and-metal medium-mu transmitting triode for RF amplification, oscillation, and modulation.

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
51 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
Transconductance
0.02 S
Amplification factor
22.5
Max plate voltage
6000 V
Max plate dissipation
2500 W
Max grid dissipation
150 W
Max cathode current
2.5 A

Promoted maximum ratings/characteristics populated from published headings; service-specific values retained in 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

1962 Eimac

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • The EIMAC [1]

    3

    The EIMAC 3CX2500A3 is an all ceramic and metal, medium-mu,

  • The EIMAC [2]

    500

    The EIMAC 3CX2500A3 is an all ceramic and metal, medium-mu,

  • dissipation rating of

    2500 W

    dissipation rating of 2500 watts. Relatively high power output as an ampli-

  • voltages. The [1]

    3

    voltages. The 3CX2500A3 is an exact replacement for the EIMAC 3X2500A3

  • voltages. The [2]

    500

    voltages. The 3CX2500A3 is an exact replacement for the EIMAC 3X2500A3

  • voltages. The [3]

    3

    voltages. The 3CX2500A3 is an exact replacement for the EIMAC 3X2500A3

  • voltages. The [4]

    500

    voltages. The 3CX2500A3 is an exact replacement for the EIMAC 3X2500A3

  • Voltage

    7.5 V

    Voltage - - - - - - - - 7.5 volts

  • Current [1]

    49 A

    Current - - - - - - - - 49 53 amperes

  • Current [2]

    53 A

    Current - - - - - - - - 49 53 amperes

  • Amplification Factor [1]

    19

    Amplification Factor - - - - - - 19 26

  • Amplification Factor [2]

    26

    Amplification Factor - - - - - - 19 26

  • Highest Frequency for Maximum Ratings

    75 MHz

    Highest Frequency for Maximum Ratings - 75 MHz

  • i li lifi DC Plate Voltage [1]

    4000 V

    i li lifi DC Plate Voltage - - - - - - 4000 5000 6000 volts

  • i li lifi DC Plate Voltage [2]

    5000 V

    i li lifi DC Plate Voltage - - - - - - 4000 5000 6000 volts

  • i li lifi DC Plate Voltage [3]

    6000 V

    i li lifi DC Plate Voltage - - - - - - 4000 5000 6000 volts

  • C°pg§gt;gzg'e':g‘ggafig i DC Plate Current [1]

    2.5 A

    C°pg§gt;gzg'e':g‘ggafig i DC Plate Current - - - - - - 2.5 2.5 2.08 amps

  • C°pg§gt;gzg'e':g‘ggafig i DC Plate Current [2]

    2.5 A

    C°pg§gt;gzg'e':g‘ggafig i DC Plate Current - - - - - - 2.5 2.5 2.08 amps

  • C°pg§gt;gzg'e':g‘ggafig i DC Plate Current [3]

    2.08 A

    C°pg§gt;gzg'e':g‘ggafig i DC Plate Current - - - - - - 2.5 2.5 2.08 amps

  • DC Grid Voltage [1]

    300 V

    DC Grid Voltage - - - - - - 300 —450 —500 volts

  • DC Grid Voltage [2]

    -450 V

    DC Grid Voltage - - - - - - 300 —450 —500 volts

  • DC Grid Voltage [3]

    -500 V

    DC Grid Voltage - - - - - - 300 —450 —500 volts

  • Class-C FM or Telegraphy (Key-down DC Grid Current* [1]

    245

    Class-C FM or Telegraphy (Key-down DC Grid Current* 245 265 180

  • Class-C FM or Telegraphy (Key-down DC Grid Current* [2]

    265

    Class-C FM or Telegraphy (Key-down DC Grid Current* 245 265 180

  • Class-C FM or Telegraphy (Key-down DC Grid Current* [3]

    180

    Class-C FM or Telegraphy (Key-down DC Grid Current* 245 265 180

  • MAXIMUM RATINGS [1]

    8 W

    MAXIMUM RATINGS 8r|\émg Power* - - - - - - 142 197 136 watts

  • MAXIMUM RATINGS [2]

    142 W

    MAXIMUM RATINGS 8r|\émg Power* - - - - - - 142 197 136 watts

  • MAXIMUM RATINGS [3]

    197 W

    MAXIMUM RATINGS 8r|\émg Power* - - - - - - 142 197 136 watts

  • MAXIMUM RATINGS [4]

    136 W

    MAXIMUM RATINGS 8r|\émg Power* - - - - - - 142 197 136 watts

  • rid Dissipation* [1]

    68 W

    rid Dissipation* - - - - - - 68 78 46 watts

  • rid Dissipation* [2]

    78 W

    rid Dissipation* - - - - - - 68 78 46 watts

  • rid Dissipation* [3]

    46 W

    rid Dissipation* - - - - - - 68 78 46 watts

  • DC PLATE VOLTAGE [1]

    6000 V

    DC PLATE VOLTAGE - 6000 VOLTS Plate Power Input - - - - - 10,000 12,500 12,500 watts

  • DC PLATE VOLTAGE [2]

    10000 V

    DC PLATE VOLTAGE - 6000 VOLTS Plate Power Input - - - - - 10,000 12,500 12,500 watts

  • DC PLATE VOLTAGE [3]

    12500 V

    DC PLATE VOLTAGE - 6000 VOLTS Plate Power Input - - - - - 10,000 12,500 12,500 watts

  • DC PLATE VOLTAGE [4]

    12500 V

    DC PLATE VOLTAGE - 6000 VOLTS Plate Power Input - - - - - 10,000 12,500 12,500 watts

  • DC PLATE CURRENT [1]

    2.5 A

    DC PLATE CURRENT - 2.5 AMPS Plate Dissipation - - - - - - 2500 2500 . 2500 watts

  • DC PLATE CURRENT [2]

    2500 A

    DC PLATE CURRENT - 2.5 AMPS Plate Dissipation - - - - - - 2500 2500 . 2500 watts

  • DC PLATE CURRENT [3]

    2500 A

    DC PLATE CURRENT - 2.5 AMPS Plate Dissipation - - - - - - 2500 2500 . 2500 watts

  • DC PLATE CURRENT [4]

    2500 A

    DC PLATE CURRENT - 2.5 AMPS Plate Dissipation - - - - - - 2500 2500 . 2500 watts

  • PLATE DISSIPATION [1]

    2500 W

    PLATE DISSIPATION - 2500 WATTS Plate Power Output - - - - - 7500 10,000 10,000 watts

  • PLATE DISSIPATION [2]

    7500 W

    PLATE DISSIPATION - 2500 WATTS Plate Power Output - - - - - 7500 10,000 10,000 watts

  • PLATE DISSIPATION [3]

    10000 W

    PLATE DISSIPATION - 2500 WATTS Plate Power Output - - - - - 7500 10,000 10,000 watts

  • PLATE DISSIPATION [4]

    10000 W

    PLATE DISSIPATION - 2500 WATTS Plate Power Output - - - - - 7500 10,000 10,000 watts

  • GRID DISSIPATION

    150 W

    GRID DISSIPATION - 150 WATTS *Approximate values.

  • FREQUENCY AMPLIFIER Bg I;Ilate \éoltage S [1]

    4000 V

    FREQUENCY AMPLIFIER Bg I;Ilate \éoltage S 4000 4500 5000 volts

  • FREQUENCY AMPLIFIER Bg I;Ilate \éoltage S [2]

    4500 V

    FREQUENCY AMPLIFIER Bg I;Ilate \éoltage S 4000 4500 5000 volts

  • FREQUENCY AMPLIFIER Bg I;Ilate \éoltage S [3]

    5000 V

    FREQUENCY AMPLIFIER Bg I;Ilate \éoltage S 4000 4500 5000 volts

  • ate Current [1]

    1.67 A

    . . . ate Current - - - - - - 1.67 1.47 1.25 amps

  • ate Current [2]

    1.47 A

    . . . ate Current - - - - - - 1.67 1.47 1.25 amps

  • ate Current [3]

    1.25 A

    . . . ate Current - - - - - - 1.67 1.47 1.25 amps

  • oororrelized Amplifier, OC Grid Voltage [1]

    450 V

    oororrelized Amplifier, OC Grid Voltage - - - - - . 450 500 —550 volts

  • oororrelized Amplifier, OC Grid Voltage [2]

    500 V

    oororrelized Amplifier, OC Grid Voltage - - - - - . 450 500 —550 volts

  • oororrelized Amplifier, OC Grid Voltage [3]

    -550 V

    oororrelized Amplifier, OC Grid Voltage - - - - - . 450 500 —550 volts

  • q ] o DC Grid Current* [1]

    180 mA

    q ] o DC Grid Current* - - . . . 180 140 150 ma

  • q ] o DC Grid Current* [2]

    140 mA

    q ] o DC Grid Current* - - . . . 180 140 150 ma

  • q ] o DC Grid Current* [3]

    150 mA

    q ] o DC Grid Current* - - . . . 180 140 150 ma

  • Class-C Telephony (Carrier conditions, Peak RF Grid Input Voltage* [1]

    685 V

    Class-C Telephony (Carrier conditions, Peak RF Grid Input Voltage* - - - 685 715 760 volts

  • Class-C Telephony (Carrier conditions, Peak RF Grid Input Voltage* [2]

    715 V

    Class-C Telephony (Carrier conditions, Peak RF Grid Input Voltage* - - - 685 715 760 volts

  • Class-C Telephony (Carrier conditions, Peak RF Grid Input Voltage* [3]

    760 V

    Class-C Telephony (Carrier conditions, Peak RF Grid Input Voltage* - - - 685 715 760 volts

  • per tube) Driving Power* - - - - o [1]

    125 W

    per tube) Driving Power* - - - - o 125 100 115 watts

  • per tube) Driving Power* - - - - o [2]

    100 W

    per tube) Driving Power* - - - - o 125 100 115 watts

  • per tube) Driving Power* - - - - o [3]

    115 W

    per tube) Driving Power* - - - - o 125 100 115 watts

  • MAXIMUM RATINGS Grid Dissipation®* [1]

    43 W

    MAXIMUM RATINGS Grid Dissipation®* - - - - - . 43 30 32 watts

  • MAXIMUM RATINGS Grid Dissipation®* [2]

    30 W

    MAXIMUM RATINGS Grid Dissipation®* - - - - - . 43 30 32 watts

  • MAXIMUM RATINGS Grid Dissipation®* [3]

    32 W

    MAXIMUM RATINGS Grid Dissipation®* - - - - - . 43 30 32 watts

  • DC PLATE VOLTAGE [1]

    5000 V

    DC PLATE VOLTAGE - 5000 VOLTS Plate Power Input - - - - - . 6670 6615 6250 watts

  • DC PLATE VOLTAGE [2]

    6670 V

    DC PLATE VOLTAGE - 5000 VOLTS Plate Power Input - - - - - . 6670 6615 6250 watts

  • DC PLATE VOLTAGE [3]

    6615 V

    DC PLATE VOLTAGE - 5000 VOLTS Plate Power Input - - - - - . 6670 6615 6250 watts

  • DC PLATE VOLTAGE [4]

    6250 V

    DC PLATE VOLTAGE - 5000 VOLTS Plate Power Input - - - - - . 6670 6615 6250 watts

  • DC PLATE CURRENT [1]

    2 A

    DC PLATE CURRENT - 2.0 AMPS Plate Dissipation S S 1670 1315 950 watts

  • DC PLATE CURRENT [2]

    1670 A

    DC PLATE CURRENT - 2.0 AMPS Plate Dissipation S S 1670 1315 950 watts

  • DC PLATE CURRENT [3]

    1315 A

    DC PLATE CURRENT - 2.0 AMPS Plate Dissipation S S 1670 1315 950 watts

  • DC PLATE CURRENT [4]

    950 A

    DC PLATE CURRENT - 2.0 AMPS Plate Dissipation S S 1670 1315 950 watts

  • PLATE DISSIPATION [1]

    1670 W

    PLATE DISSIPATION - 1670 VOLIS Plate Power Output - - - - - 5000 5300 5300 watts

  • PLATE DISSIPATION [2]

    5000 W

    PLATE DISSIPATION - 1670 VOLIS Plate Power Output - - - - - 5000 5300 5300 watts

  • PLATE DISSIPATION [3]

    5300 W

    PLATE DISSIPATION - 1670 VOLIS Plate Power Output - - - - - 5000 5300 5300 watts

  • PLATE DISSIPATION [4]

    5300 W

    PLATE DISSIPATION - 1670 VOLIS Plate Power Output - - - - - 5000 5300 5300 watts

  • AMPLIFIER OR MODULATOR DC Plate Voltage [1]

    4000 V

    AMPLIFIER OR MODULATOR DC Plate Voltage - - - - - . 4000 5000 6000 volts

  • AMPLIFIER OR MODULATOR DC Plate Voltage [2]

    5000 V

    AMPLIFIER OR MODULATOR DC Plate Voltage - - - - - . 4000 5000 6000 volts

  • AMPLIFIER OR MODULATOR DC Plate Voltage [3]

    6000 V

    AMPLIFIER OR MODULATOR DC Plate Voltage - - - - - . 4000 5000 6000 volts

  • Class-AB or B U DC Grid Voltage! [1]

    -150 V

    Class-AB or B U DC Grid Voltage! - - - - - - —150 —190 -—240 volts

  • Class-AB or B U DC Grid Voltage! [2]

    -190 V

    Class-AB or B U DC Grid Voltage! - - - - - - —150 —190 -—240 volts

  • Class-AB or B U DC Grid Voltage! [3]

    -240 V

    Class-AB or B U DC Grid Voltage! - - - - - - —150 —190 -—240 volts

Data set 02

1965 Eimac Tube Manual

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Heater/filament voltage

    7.5 V

  • Heater/filament current

    53 A

  • Amplification factor

    26

  • Transconductance

    20000 uS

Capacitance

  • Input/grid-cathode capacitance

    29.2 pF

  • Output/plate-cathode capacitance

    40.2 pF

  • Feedback/grid-plate capacitance

    1.2 pF

Other

  • Maximum plate voltage

    6000 V

  • Maximum plate dissipation

    2500 W

  • Maximum grid dissipation

    150 W

  • Maximum plate/cathode current

    2.5 A

  • Frequency for maximum ratings

    75 MHz

  • Typical RF plate voltage

    6000 V

    ClassC

  • Typical RF plate current

    2.08 A

    ClassC

  • Typical RF output power

    10000 W

    ClassC

  • AF maximum-signal output, two tubes

    13000 W

    ClassB;TwoTubes