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Power - Triode ·Triode

7685

Forced-air-cooled low-mu linear power triode for Class AB and B audio or RF amplification. Manufacturer applications include broadcast, single-sideband transmitters, ultrasonic generators, and sonar pulse amplifiers.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
-

Description

Westinghouse 7685 @ QOctober 1, 1940 LINEAR LOW-MU TRIODE TYPE 7685 The 7685 is a low-mu triode designed for service as a class AB, or class B linear amplifier in audio or r-f service. The 7685 is well suited for application in broedcast and single-sideband transmitters, ultrasonic gen- erators, and sonar pulse amplifiers. The forced air cooled anode is capable of dissipating 800 watts., The cathode is of indirectiy-heated, oxide-coated, unipotential design. Maximum rotings apply te 60 megacycles. ELECTRICAL: CLASS ABPOWER AMPLIFIER T Cathede. . . ..... ..o Oxide-Coated Unipotential MAXIMUM RATINGS: Heater: Absaolute Maximum Valyes Voltage . o . o vt it e e e 5.0 VYolis DC Plote Voltage . .. ... ......... 4.0 max. Kilovolts Current . . . e e e e e e 8.0 Amperes DC Grid Voltage® . . . . .. ... 0.0 ~800 max Volts Starting Current (Max.) . . .. .. ... ..., ... 24 Amperes DC Plate Current. . . .. oo i o iy v v 600 max Ma. Resistance (Cold} . . .. ... .. .. ... ..... 0.1 Ohm DC Plate Power

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
-
Nominal heater current
-
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
6.5
Max plate dissipation
600 W
Max cathode current
635 mA

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

  • The

    7685

    The 7685 is a low-mu triode designed for service as a class AB, or class B linear amplifier in audio or r-f

  • erators, and sonar pulse amplifiers. The forced air cooled anode is capable of dissipating

    800

    erators, and sonar pulse amplifiers. The forced air cooled anode is capable of dissipating 800 watts., The

  • cathode is of indirectiy-heated, oxide-coated, unipotential design. Maximum rotings apply te

    60

    cathode is of indirectiy-heated, oxide-coated, unipotential design. Maximum rotings apply te 60 megacycles.

  • Voltage . o . o vt it e e e

    5

    Voltage . o . o vt it e e e 5.0 VYolis

  • DC Plote Voltage

    4

    DC Plote Voltage . .. ... ......... 4.0 max. Kilovolts

  • Current . . . e e e e e e

    8

    Current . . . e e e e e e 8.0 Amperes

  • DC Grid Voltage®

    800

    DC Grid Voltage® . . . . .. ... 0.0 ~800 max Volts

  • Starting Current (Max.) . . .. .. ... ...,

    24

    Starting Current (Max.) . . .. .. ... ..., ... 24 Amperes

  • DC Plate Power Input®

    1.5

    DC Plate Power Input®. . . .. ....... 1.5 max. Kilowatts

  • Minimum Filoment Heating Time . . . . . . ,

    120

    Minimum Filoment Heating Time . . . . . . , 120 Seconds

  • Plate Dissipation#,

    600

    Plate Dissipation#, . ... .......... 600 max Watts

  • Amplification Facter

    6.5

    Amplification Facter. . . . . ... ... ........ 6.5

  • Cathode to Plate . . . .. ... .., ..,

    550

    Cathode to Plate . . . .. ... .., .., .. 0.6 0.6 papf DC Grid ¥oltage . . .. ... ... .o i ~550 Yolts

  • Peck A-F Grid-to-Grid Voltage. . . . ... ...,

    1100

    Peck A-F Grid-to-Grid Voltage. . . . ... ..., 1100 Yolts

  • Maximum Signal Plate Current

    0.635

    Maximum Signal Plate Current. . .. .. ... ... 0.635 Amperes

  • Maximum Incoming Air Temperoture

    45

    Maximum Incoming Air Temperoture . . . . .. ... .. ... 45°C

  • Maximum Signal Power Qutput

    1550

    Maximum Signal Power Qutput. . . . ... ... .. 1550 Watts

  • Maximum Glass Temperature . ... ....,

    180

    Maximum Glass Temperature . ... ....,... 180 °C a The tube may be supported aither by the anode or by use of o

  • .640° DIA.

    640

    .640° DIA.

Characteristic

  • Resistance (Cold}

    0.1

    Resistance (Cold} . . .. ... .. .. ... ..... 0.1 Ohm

  • Effectiva Plate-to-Plate LLoad Resistance

    12300

    Effectiva Plate-to-Plate LLoad Resistance. . .. 12300 Ohms

  • Plate Dissipation

    100000

    Plate Dissipation. . . . . ... ..... 200 400 400 Watts [::] Grid circuit resistance should not exceed 100000 ohms,