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Heptode ·Heptode

6687

Dual-control heptode designed specifically as a gated amplifier in computer circuits, allowing one control signal to gate amplification of another.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B7G
Base pins
-
Nominal heater
6.3 V / 270 mA

Description

6687 is listed in the supplied Amperex material as a dual-control heptode for gated amplifier service. Published ratings and characteristics were captured from the supplied table.

Socket description

Miniature 7-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B7G
Base pins
-
Nominal heater voltage
6.3 V
Nominal heater current
270 mA
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

Heptode

X-ray radiationInterelectrode capacitances
Max plate voltage
250 V

Published ratings and characteristics promoted from the supplied Rogers/Rogers Majestic source.

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

1958 Amperex Industrial

Published operating points and test conditions from this source.

SECTION 1

Heptode

Characteristic

  • Heater/filament voltage

    6.3 V

    Published rating

  • Heater/filament current

    270 mA

    Published rating

  • Control-grid cutoff voltage

    -10 V

    GatedAmplifier

Other

  • Plate voltage

    150 V

    GatedAmplifier

  • Plate current both controls at zero

    5.75 mA

    GatedAmplifier

Data set 02

1959 Rogers

Published operating points and test conditions from this source.

SECTION 1

Heptode

Characteristic

  • HeaterOrFilamentVoltage

    6.3 V

  • HeaterOrFilamentCurrent

    270 mA

  • Application

    Gated amplifier

    Computer

Data set 03

1963 Amperex Condensed

Published operating points and test conditions from this source.

SECTION 1

Heptode

Characteristic

  • Heater voltage

    6.3 V

    Published rating

  • Heater current

    270 mA

    Published rating

  • Published characteristic value

    3.4

    GatedAmplifier

  • Published characteristic value 2

    7.6

    GatedAmplifier

  • Published characteristic value 3

    1

    GatedAmplifier

Other

  • Maximum plate voltage

    250 V

    GatedAmplifier

  • Control-grid voltage

    -100 V

    GatedAmplifier