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Power - Pentode Single (NOT beam) (under 10W) ·Pentode

6686

Power/output pentode designed for audio, broadband, telephone, industrial, or general power-amplifier service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
5686
Socket code
-
Base pins
-
Nominal heater
6.3 V / 375 mA

Description

6686 is listed in the supplied Amperex material as a premium-quality power pentode. Published ratings and characteristics were captured from the supplied table.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
5686
Socket code
-
Base pins
-
Nominal heater voltage
6.3 V
Nominal heater current
375 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

5686 - 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
45000 Ω
Transconductance
0.0031 S
Amplification factor
36
Max plate voltage
250 V
Max screen voltage
250 V
Max plate dissipation
4.5 W

Published maximum ratings, representative operating conditions, and available capacitance/rectifier data reviewed.

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

    210 V

    Published table

  • Screen voltage

    210 V

    Published table

  • Plate current

    30 mA

    Published table

  • Power output

    36 W

    Published table

Characteristic

  • Plate resistance

    11000 ohm

    Published table

  • Heater/filament voltage

    6.3 V

    Published rating

  • Heater/filament current

    375 mA

    Published rating

Data set 02

195X General Electric Essential Characteristics

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Maximum plate voltage

    250 V

    Published handbook rating

  • Maximum screen voltage

    250 V

    Published handbook rating

  • Plate voltage

    250 V

    ClassA

  • Screen voltage

    250 V

    ClassA

  • Control-grid bias

    12.5 V

    ClassA

  • Plate current

    27 mA

    ClassA

  • Screen current

    3 mA

    ClassA

  • Load resistance

    9000 ohm

    ClassA

  • Power output

    2.7 W

    ClassA

  • Class-C plate voltage

    250 V

    ClassC RFPower

  • Class-C screen voltage

    250 V

    ClassC RFPower

  • Class-C control-grid bias

    50 V

    ClassC RFPower

  • Class-C plate current

    40 mA

    ClassC RFPower

  • Class-C screen current

    10.5 mA

    ClassC RFPower

  • Class-C input signal power

    0.15 W

    ClassC RFPower

  • Class-C power output

    6.5 W

    ClassC RFPower

Characteristic

  • Plate resistance

    45000 ohm

    Published handbook characteristic

  • Transconductance

    3100 µS

    Published handbook characteristic

  • Heater/filament voltage

    6.3 V

    Published heater/filament rating

  • Heater/filament current

    350 mA

    Published heater/filament rating

Capacitance

  • Input capacitance

    6.5 pF

    Published capacitance column

  • Output capacitance

    8.5 pF

    Published capacitance column

  • Grid-to-plate capacitance

    0.08 pF

    Published capacitance column

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

    375 mA

    Published rating

  • Published characteristic value

    11.5

    PremiumQuality

  • Published characteristic value 2

    6.5

    PremiumQuality

Other

  • Maximum plate voltage

    210 V

    PremiumQuality

  • Plate voltage

    210 V

    PremiumQuality

  • Plate current

    30 mA

    PremiumQuality