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

7748

Massive water-cooled Westinghouse power triode for Class B and C oscillator, amplifier, and modulator service. Rated around 35 kW plate dissipation and 12.5 kV, it handles multi-kilowatt industrial and transmitting RF power.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
8 V / 150 A

Description

Westinghouse — 7748 February 15, 1961 POWER AMPLIFIER TRIODE TYPE 7748 The type 7748 is a three electrode tube designed for service as an oscillator, amplifier or modulator in Class B & C operation. The anode is water cooled with an integral water jacket and is capable of dissipating 35 kilowatts during C.C.5. The cathode is a thoriated tungsten filament which may be operated either with d-c or single-phase a-c. Maximum ratings apply to 30 megacycles. ELECTRICAL: MAXIMUM RATINGS: Cothode. . vu s v e e v nnninan Thetiated Tungstan Filament Absolute Moximum Values Filament; DC Plate Voltage. . « v v v v o v v v 12.5 max. Kilovolts Voltage . v v vt s i vt v s sa e st 8.0 Yolts DC Plate Current, . . v o v oo vt s v s 10 mex. Amperas CURTONE & 4 v v v e st e bt st o v s nnssanacan 150 Amperes DCGrid Voltage . . v v v v v ivevnenn =3000 mox. Velts Minimum Heating Time . . .« o oo v e u v a v e 15 Seconds DCGrid Current .. o v v et v v 0 av s 1.25 max. Ampeares Amplification Foctor ..t 0 v e

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
8 V
Nominal heater current
150 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
20
Max plate voltage
12500 V
Max plate dissipation
35000 W
Max cathode current
10 A

Source-derived physical/electrical section.

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

1947 Westinghouse

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • POWER AMPLIFIER TRIODE TYPE

    7748

    POWER AMPLIFIER TRIODE TYPE 7748

  • The type

    7748

    The type 7748 is a three electrode tube designed for service as an oscillator, amplifier or modulator in Class

  • kilowatts during C.C

    5

    kilowatts during C.C.5. The cathode is a thoriated tungsten filament which may be operated either with d-c or

  • single-phase a-c. Maximum ratings apply to

    30

    single-phase a-c. Maximum ratings apply to 30 megacycles.

  • Filament; DC Plate Voltage. . « v v v v o v v v

    12.5

    Filament; DC Plate Voltage. . « v v v v o v v v 12.5 max. Kilovolts

  • Voltage . v v vt s i vt v s sa e st

    10

    Voltage . v v vt s i vt v s sa e st 8.0 Yolts DC Plate Current, . . v o v oo vt s v s 10 mex. Amperas

  • CURTONE &

    3000

    CURTONE & 4 v v v e st e bt st o v s nnssanacan 150 Amperes DCGrid Voltage . . v v v v v ivevnenn =3000 mox. Velts

  • Minimum Heating Time . . .« o oo v e u v a v e

    0

    Minimum Heating Time . . .« o oo v e u v a v e 15 Seconds DCGrid Current .. o v v et v v 0 av

  • s

    1.25

    s 1.25 max. Ampeares

  • Amplification Foctor ..t

    80

    Amplification Foctor ..t 0 v e e v nninsen 20 Plate Power Input « .« v vt v e v v avas 80 mox. Kilowatts

  • DC Grid Voltoge . . . . . . _

    1300

    DC Grid Voltoge . . . . . . _800 ~1100 —1300

  • MECHANICAL: Peak R.F. Grid Voltage

    1700

    MECHANICAL: Peak R.F. Grid Voltage. . 1250 1500 1700 Yolts

  • Mounting Position . . ...uuneiiaa .. Vertical, Anode Down DC Plate Current,

    4.25

    Mounting Position . . ...uuneiiaa .. Vertical, Anode Down DC Plate Current, .. ... 5.5 4.7 4.25 Amperes

  • Typeof Cooling. . -« v vt v i tn vt i s v e r v oes Water DC Grid Current , , ...,

    0.59

    Typeof Cooling. . -« v vt v i tn vt i s v e r v oes Water DC Grid Current , , ..., 0.875 0.58 0.59 Ampores

  • Water Flow Required

    970

    Water Flow Required .. ..... .00 N 30 GPM Driving Power, . . . .. .. 1050 850 970 Watts

  • Static Pressure (

    446.5

    Static Pressure (0t 30 GPM). .+« « v i v e v vt naan 8 PS5l Power Qutput . .. ... u 33,5 40 446.5 Kilowatta

  • Maximum Qutiet-Water Temperature . . . o v v v v v o v vs o

    70

    Maximum Qutiet-Water Temperature . . . o v v v v v o v vs o 70 °C

  • Maximum Grid and Filament Seol Temperature

    180

    Maximum Grid and Filament Seol Temperature . ... .... 180 °C

  • N With Plate Amps {

    8

    N With Plate Amps {80~ 8.0 Volis

  • N \/’ With Plate Amps » B

    0

    N \/’ With Plate Amps » B0 - -+ i10.0 Voits

  • 1400 b N \1“'>>< At Filamen? Volts =80 - --- 180 Amperes

    180

    1400 b N \1“'>>< At Filamen? Volts =80 - --- 180 Amperes

  • P ’/"X’ At Filament Volts =

    100

    P ’/"X’ At Filament Volts =100 ---

  • - 210 Amperes

    210

    - 210 Amperes

  • \(/ e T ,’\/

    200

    \(/ e T ,’\/ 200 Plate Amperes

  • e /)’/

    4

    e /)’/4,\’ :\" I Grid Amperes mmm e e

Characteristic

  • Diroct Intaralectrode Capacitances: Plato Dissipation ... .vvuvvvvanns

    35

    Diroct Intaralectrode Capacitances: Plato Dissipation ... .vvuvvvvanns 35 wmox, Kilowatts