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

YU148

Forced-air-cooled high-mu power triode for grounded-grid VHF amplifier, oscillator, and modulator service. Approximately 6 kW plate dissipation, 7 kV capability, and very high gain support powerful professional RF stages.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
7 V / 78 A

Description

The EIMAC YU148 is a forced-air-cooled high-mu power triode for grounded-grid vhf amplifier, oscillator, and modulator service.

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 V
Nominal heater current
78 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
200
Max plate voltage
7000 V
Max plate dissipation
6000 W
Max grid dissipation
225 W
Max cathode current
3.5 A

Promoted from the highest applicable published maximum-rating/service block; additional service-specific limits and operating conditions are 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

1975 Eimac Tube Manual

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Heater voltage nominal

    7 V

  • Heater current nominal

    78 A

  • Amplification factor

    200

Capacitance

  • Input/grid-cathode capacitance

    42 pF

  • Output/plate-cathode capacitance

    0.28 pF

  • Grid-plate/feedback capacitance

    24.5 pF

Other

  • Maximum plate voltage

    7000 V

  • Maximum plate dissipation

    6000 W

  • Maximum grid dissipation

    225 W

  • Maximum cathode or pulse plate current

    3.5 A

  • Maximum rated frequency

    0.108 GHz

  • Typical RF frequency

    108 MHz

    ClassC;CathodeDriven

  • Typical plate voltage

    6000 V

    ClassC

  • Typical grid voltage

    -100 V

    ClassC

  • Typical plate current

    2.56 A

    ClassC

  • Typical grid current

    480 mA

    ClassC

  • Typical peak RF cathode voltage

    340 V

    ClassC

  • Typical plate dissipation

    3900 W

    ClassC

  • Typical useful output power

    12000 W

    ClassC

  • Typical driving power

    800 W

    ClassC

  • Load impedance

    1200 ohm

    ClassC

  • Drive impedance

    77 ohm

    ClassC

Data set 02

1976 Eimac Tube Manual

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Heater voltage nominal

    7 V

  • Heater current nominal

    78 A

  • Amplification factor

    200

Capacitance

  • Input/grid-cathode capacitance

    42 pF

  • Output/plate-cathode capacitance

    0.28 pF

  • Grid-plate/feedback capacitance

    24.5 pF

Other

  • Maximum plate voltage

    7000 V

  • Maximum plate dissipation

    6000 W

  • Maximum grid dissipation

    225 W

  • Maximum cathode or pulse plate current

    3.5 A

  • Maximum rated frequency

    0.108 GHz

  • Typical RF frequency

    108 MHz

    ClassC;CathodeDriven

  • Typical plate voltage

    6000 V

    ClassC

  • Typical grid voltage

    -100 V

    ClassC

  • Typical plate current

    2.56 A

    ClassC

  • Typical grid current

    480 mA

    ClassC

  • Typical peak RF cathode voltage

    340 V

    ClassC

  • Typical plate dissipation

    3900 W

    ClassC

  • Typical useful output power

    12000 W

    ClassC

  • Typical driving power

    800 W

    ClassC

  • Load impedance

    1200 ohm

    ClassC

  • Drive impedance

    77 ohm

    ClassC

Data set 03

199X Svetlana

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Current @

    7 V

    modulator service. A modern mesh filament

  • Input

    42 pF

    modulator service. A modern mesh filament

  • Output

    24.5 pF

    modulator service. A modern mesh filament

  • Feedback

    0.28 pF

    modulator service. A modern mesh filament

Other

  • DC Plate voltage

    7000 V

    Maximum Ratings

  • DC Plate current

    3.5 A

    Maximum Ratings

  • Plate dissipation

    6000 W

    Maximum Ratings

  • Grid dissipation

    225 W

    Maximum Ratings

  • (Frequencies to

    110 MHz

    Typical operation

  • Plate voltage 4800 5700

    6000 V

    Typical operation

  • Grid voltage 0 0

    -100 V

    Typical operation

  • Plate current 2.3 2.5

    2.56 A

    Typical operation

  • Grid current* 0.32 0.33

    480 mA

    Typical operation

  • Peak RF cathode voltage* 215 224

    340 V

    Typical operation

  • Calculated driving power* 500 600

    800 W

    Typical operation

  • Plate dissipation 3200 4100

    3900 W

    Typical operation

  • Useful output power 8000 10000

    12000 W

    Typical operation

  • below

    250 ˚C

    Typical operation

  • maintain these temperatures below

    225 ˚C

    Typical operation

  • with an inlet-air temperature of

    50 ˚C

    Typical operation

  • tabulated. At frequencies above

    40 MHz

    Typical operation