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

304TH

Eimac medium-mu power triode for audio power amplification, modulation, RF amplification, and oscillator service. With about 300 W plate dissipation and 3 kV capability, it provides substantial linear or transmitting power through roughly 40 MHz.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
SPECIAL4
Base pins
-
Nominal heater
10 V / 12.5 A

Description

The Eimac 304TH is a medium-mu power triode for audio-frequency power-amplifier or modulator and radio-frequency power-amplifier or oscillator service.

Socket description

Special 4-contact transmitting-tube base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
SPECIAL4
Base pins
-
Nominal heater voltage
10 V
Nominal heater current
12.5 A
Parallel heater voltage
5 V
Parallel heater current
25 A
Series capable
Yes

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
0.0167 S
Amplification factor
20
Max plate voltage
3000 V
Max plate dissipation
300 W

Published maximum ratings and characteristics audited; additional applicable numerical data retained in parameter table.

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 Eimac Tubes

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Current [1]

    25 A

    Current - - 25.0 or 12.5 amperes

  • Current [2]

    12.5 A

    Current - - 25.0 or 12.5 amperes

  • Grid -Pla te [1]

    10

    Grid -Pla te 10 .2 fLfLf

  • Grid -Pla te [2]

    2

    Grid -Pla te 10 .2 fLfLf

  • Grid-Filament

    13.5

    Grid-Filament 13.5 fL fLf

  • Plate-Filament [1]

    0

    Plate-Filament - 0 .7 fLfL f

  • Plate-Filament [2]

    7

    Plate-Filament - 0 .7 fLfL f

  • Transconductance ( [1]

    1

    Transconductance (1 \)=1 .0 amp., E\)=3000, e c =-40) 16,700 fLmhos

  • Transconductance ( [2]

    1

    Transconductance (1 \)=1 .0 amp., E\)=3000, e c =-40) 16,700 fLmhos

  • Transconductance ( [3]

    0

    Transconductance (1 \)=1 .0 amp., E\)=3000, e c =-40) 16,700 fLmhos

  • Transconductance ( [4]

    3000

    Transconductance (1 \)=1 .0 amp., E\)=3000, e c =-40) 16,700 fLmhos

  • Transconductance ( [5]

    -40

    Transconductance (1 \)=1 .0 amp., E\)=3000, e c =-40) 16,700 fLmhos

  • Transconductance ( [6]

    16700

    Transconductance (1 \)=1 .0 amp., E\)=3000, e c =-40) 16,700 fLmhos

  • Frequency for Maximum Ratings

    40 MHz

    Frequency for Maximum Ratings 40 mc

  • D-C Pla te Voltage [1]

    1500 V

    D-C Pla te Voltage 1500 2000 3000 3000 volts

  • D-C Pla te Voltage [2]

    2000 V

    D-C Pla te Voltage 1500 2000 3000 3000 volts

  • D-C Pla te Voltage [3]

    3000 V

    D-C Pla te Voltage 1500 2000 3000 3000 volts

  • D-C Pla te Voltage [4]

    3000 V

    D-C Pla te Voltage 1500 2000 3000 3000 volts

  • Max.-Signal D-C Plate Cu rren t, pe r tube" - • • •

    900

    Max.-Signal D-C Plate Cu rren t, pe r tube" - • • • 900 mao

  • Plate Dissipation, pe r tube " • • •

    300 W

    Plate Dissipation, pe r tube " • • • 300 watts

  • D-C Grid Voltage (approx. ) [1]

    -65 V

    D-C Grid Voltage (approx. ) -65 -90 -150 volts

  • D-C Grid Voltage (approx. ) [2]

    -90 V

    D-C Grid Voltage (approx. ) -65 -90 -150 volts

  • D-C Grid Voltage (approx. ) [3]

    -150 V

    D-C Grid Voltage (approx. ) -65 -90 -150 volts

  • Peak A -F Grid Inpu t Voltage [1]

    330 V

    Peak A -F Grid Inpu t Voltage 330 350 420 volts

  • Peak A -F Grid Inpu t Voltage [2]

    350 V

    Peak A -F Grid Inpu t Voltage 330 350 420 volts

  • Peak A -F Grid Inpu t Voltage [3]

    420 V

    Peak A -F Grid Inpu t Voltage 330 350 420 volts

  • Zero-Signal D-C Plate Curren t [1]

    267

    Zero-Signal D-C Plate Curren t - 267 200 134 ma o

  • Zero-Signal D-C Plate Curren t [2]

    200

    Zero-Signal D-C Plate Curren t - 267 200 134 ma o

  • Zero-Signal D-C Plate Curren t [3]

    134

    Zero-Signal D-C Plate Curren t - 267 200 134 ma o

  • Max.-Signal Driv ing Power ( ap p rox .) [1]

    17 W

    Max.-Signal Driv ing Power ( ap p rox .) - 17 12 6 wat ts

  • Max.-Signal Driv ing Power ( ap p rox .) [2]

    12 W

    Max.-Signal Driv ing Power ( ap p rox .) - 17 12 6 wat ts

  • Max.-Signal Driv ing Power ( ap p rox .) [3]

    6 W

    Max.-Signal Driv ing Power ( ap p rox .) - 17 12 6 wat ts

  • Effective Load, Plate-to-Pla te [1]

    2840

    Effective Load, Plate-to-Pla te - 2840 4820 10200 ohms

  • Effective Load, Plate-to-Pla te [2]

    4820

    Effective Load, Plate-to-Pla te - 2840 4820 10200 ohms

  • Effective Load, Plate-to-Pla te [3]

    10200

    Effective Load, Plate-to-Pla te - 2840 4820 10200 ohms

  • Max.-Signal Plate Powe r Outpu t [1]

    1000

    Max.-Signal Plate Powe r Outpu t 1000 1200 1400 wat ts

  • Max.-Signal Plate Powe r Outpu t [2]

    1200

    Max.-Signal Plate Powe r Outpu t 1000 1200 1400 wat ts

  • Max.-Signal Plate Powe r Outpu t [3]

    1400

    Max.-Signal Plate Powe r Outpu t 1000 1200 1400 wat ts

  • D-C Plate Vol tage [1]

    1500

    D-C Plate Vol tage 1500 2000 3000 3000 volts

  • D-C Plate Vol tage [2]

    2000

    D-C Plate Vol tage 1500 2000 3000 3000 volts

  • D-C Plate Vol tage [3]

    3000

    D-C Plate Vol tage 1500 2000 3000 3000 volts

  • D-C Plate Vol tage [4]

    3000

    D-C Plate Vol tage 1500 2000 3000 3000 volts

  • D-C Plate Current [1]

    667 mA

    D-C Plate Current 667 600 500 900 ma o

  • D-C Plate Current [2]

    600 mA

    D-C Plate Current 667 600 500 900 ma o

  • D-C Plate Current [3]

    500 mA

    D-C Plate Current 667 600 500 900 ma o

  • D-C Plate Current [4]

    900 mA

    D-C Plate Current 667 600 500 900 ma o

  • D-C Grid Current [1]

    115 mA

    D-C Grid Current 115 125 135 170 mao

  • D-C Grid Current [2]

    125 mA

    D-C Grid Current 115 125 135 170 mao

  • D-C Grid Current [3]

    135 mA

    D-C Grid Current 115 125 135 170 mao

  • D-C Grid Current [4]

    170 mA

    D-C Grid Current 115 125 135 170 mao

  • D-C Grid Voltage [1]

    -125 V

    D-C Grid Voltage -125 -200 -300 volts

  • D-C Grid Voltage [2]

    -200 V

    D-C Grid Voltage -125 -200 -300 volts

  • D-C Grid Voltage [3]

    -300 V

    D-C Grid Voltage -125 -200 -300 volts

  • Plate Power Outpu t [1]

    700 W

    Plate Power Outpu t - 700 900 1200 watts

  • Plate Power Outpu t [2]

    900 W

    Plate Power Outpu t - 700 900 1200 watts

  • Plate Power Outpu t [3]

    1200 W

    Plate Power Outpu t - 700 900 1200 watts

  • Plate Input [1]

    1000

    Plate Input 1000 1200 1500 watts

  • Plate Input [2]

    1200

    Plate Input 1000 1200 1500 watts

  • Plate Input [3]

    1500

    Plate Input 1000 1200 1500 watts

  • Plate Dissipation [1]

    300 W

    Plate Dissipation - 300 300 300 300 watts

  • Plate Dissipation [2]

    300 W

    Plate Dissipation - 300 300 300 300 watts

  • Plate Dissipation [3]

    300 W

    Plate Dissipation - 300 300 300 300 watts

  • Plate Dissipation [4]

    300 W

    Plate Dissipation - 300 300 300 300 watts

  • Peak R. F. Grid Input Voltage, (approx.) [1]

    250 V

    Peak R. F. Grid Input Voltage, (approx.) - 250 325 395 volts

  • Peak R. F. Grid Input Voltage, (approx.) [2]

    325 V

    Peak R. F. Grid Input Voltage, (approx.) - 250 325 395 volts

  • Peak R. F. Grid Input Voltage, (approx.) [3]

    395 V

    Peak R. F. Grid Input Voltage, (approx.) - 250 325 395 volts

  • Driving Power, (approx.l [1]

    25 W

    Driving Power, (approx.l 25 39 53 watts

  • Driving Power, (approx.l [2]

    39 W

    Driving Power, (approx.l 25 39 53 watts

  • Driving Power, (approx.l [3]

    53 W

    Driving Power, (approx.l 25 39 53 watts

  • power output and grid driv ing power ~ [1]

    70 W

    power output and grid driv ing power ~ 70 i,MA C 304TN-+-

  • power output and grid driv ing power ~ [2]

    304 W

    power output and grid driv ing power ~ 70 i,MA C 304TN-+-

  • at plate voltag es of [1]

    1500

    at plate voltag es of 1500, 20 00 and a:

  • at plate voltag es of [2]

    20

    at plate voltag es of 1500, 20 00 and a:

  • at plate voltag es of [3]

    0

    at plate voltag es of 1500, 20 00 and a:

  • bined grid and bias losses only. The (!) P.. " [1]

    2

    bined grid and bias losses only. The (!) P.. "2 8 0 W 70 125

  • bined grid and bias losses only. The (!) P.. " [2]

    8

    bined grid and bias losses only. The (!) P.. "2 8 0 W 70 125

  • bined grid and bias losses only. The (!) P.. " [3]

    0

    bined grid and bias losses only. The (!) P.. "2 8 0 W 70 125

  • bined grid and bias losses only. The (!) P.. " [4]

    70

    bined grid and bias losses only. The (!) P.. "2 8 0 W 70 125

  • bined grid and bias losses only. The (!) P.. " [5]

    125

    bined grid and bias losses only. The (!) P.. "2 8 0 W 70 125

  • Published value

    -1

    -1 PLATE

Data set 02

1962 Eimac

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Frequency for Maximum Ratings

    40 MHz

Other

  • Maximum DC Plate Current

    900 mA

Capacitance

  • Grid-Plate Capacitance

    10.2 pF

  • Grid-Filament Capacitance

    13.5 pF

  • Plate-Filament Capacitance

    0.7 pF