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Voltage Pentode ·Pentode

6689

Long-life wideband pentode developed for professional telephone and communications amplifier service with dependable continuous-duty operation.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B9A
Base pins
-
Nominal heater
6.3 V / 300 mA

Description

6689 is listed in the supplied Amperex material as a wide-band premium amplifier pentode. Published ratings and characteristics were captured from the supplied table.

Socket description

Small-button Noval 9-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B9A
Base pins
-
Nominal heater voltage
6.3 V
Nominal heater current
300 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

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
2100 Ω
Transconductance
0.009 S
Amplification factor
34
Max plate voltage
210 V
Max plate dissipation
2.1 W

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

Pentode

Other

  • Maximum plate voltage

    210 V

    Published table

  • Plate voltage

    120 V

    Published table

  • Screen voltage

    210 V

    Published table

  • Plate current

    16 mA

    Published table

  • Power output

    34 W

    Published table

Characteristic

  • Plate resistance

    9000 ohm

    Published table

  • Heater/filament voltage

    6.3 V

    Published rating

  • Heater/filament current

    300 mA

    Published rating

Data set 02

1959 Rogers

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • HeaterOrFilamentVoltage

    6.3 V

  • HeaterOrFilamentCurrent

    300 mA

  • Service

    Telephone equipment

    LongLife

Data set 03

1963 Amperex Condensed

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • Heater voltage

    6.3 V

    Published rating

  • Heater current

    300 mA

    Published rating

  • Plate resistance

    9000 ohm

    WideBandAmplifier

  • Power/output characteristic

    34

    WideBandAmplifier

Other

  • Plate voltage

    120 V

    WideBandAmplifier

  • Screen voltage

    210 V

    WideBandAmplifier

  • Plate current

    10 mA

    WideBandAmplifier