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Power - Beam (NOT sweep) ·BeamPower

6550

High-power beam tetrode designed for audio-frequency output amplification, widely used in high-fidelity and professional amplifiers requiring substantial Class-AB power.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
IO
Base pins
8
Nominal heater
6.3 V / 1.6 A

Description

Industrial beam power tube for output stages of high-fidelity audio amplifiers.

Socket description

International Octal

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
IO
Base pins
8
Nominal heater voltage
6.3 V
Nominal heater current
1.6 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

Beam Power

X-ray radiationInterelectrode capacitances
Plate resistance
15000 Ω
Transconductance
0.011 S
Amplification factor
8
Max plate voltage
660 V
Max screen voltage
440 V
Max plate dissipation
42 W
Max screen dissipation
10 W
Max cathode current
190 mA

Promoted from published typical characteristics and limiting values in 6550.pdf; repeated identical physical sections are compressed where applicable.

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

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Beam Power

Other

  • Heater voltage

    6.3 V

    Nominal

  • Heater current

    1.6 A

    Nominal

  • Plate voltage

    250 V

    Published operating table; OperatingPoint1

  • Screen voltage

    250 V

    Published operating table; OperatingPoint1

  • Maximum intermittent screen dissipation

    10 W

    MusicOrSpeechPeaks

Characteristic

  • Plate current

    140 mA

    Published operating table; OperatingPoint1

Data set 02

1966 Tung Sol Electronic Tubes 4 of 4

Published operating points and test conditions from this source.

SECTION 1

Beam Power

Characteristics

  • VOLTAGE OPERATION — published value 1

    6.3 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • VOLTAGE OPERATION — published value 2

    0.6 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • PLATE VOLTAGE, DC

    660 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • GRID 1 VOLTAGE, DC — published value 1

    -300 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • GRID 1 VOLTAGE, DC — published value 2

    0 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • PLATE DISSIPATION

    42 W

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • CATHODE CURRENT, DC

    190 mA

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • FIXED BIAS

    50 ohm

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • SELF BIAS

    250 ohm

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • BULB TEMPERATURE

    250 C

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • PLATE VOLTAGE

    250 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • GRID 2 VOLTAGE

    250 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • GRID 1 VOLTAGE

    -14 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • PLATE CURRENT

    140 mA

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • GRID 2 CURRENT

    12 mA

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • PLATE RESISTANCE, APPROX.

    15000 ohm

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • TRIODE AMPLIFICATION FACTOR

    8

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • GRID 1 VOLTAGE FOR 1 MA PLATE CURRENT

    -40 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • PLATE VOLTAGE, DC — published value 1

    250 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • PLATE VOLTAGE, DC — published value 2

    400 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • GRID 2 VOLTAGE, OC — published value 1

    250 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • GRID 2 VOLTAGE, OC — published value 2

    225 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • GRID 1 VOLTAGE, DC — published value 1

    -14 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • GRID 1 VOLTAGE, DC — published value 2

    -16.5 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • PEAK SIGNAL VOLTAGE — published value 1

    14 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • PEAK SIGNAL VOLTAGE — published value 2

    16.5 V

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

  • ZERO-SIGNAL PLATE CURRENT, DC — published value 1

    140 mA

    Published datasheet table value; multiple values on a source row represent separate limits or operating conditions.

Data set 03

1971 RCA HB3 Binder 3 of 7

Published operating points and test conditions from this source.

SECTION 1

Beam Power

Other

  • Heater voltage

    6.3 V

    Nominal

  • Heater current

    1.6 A

    Nominal

  • Maximum plate voltage

    600 V

    Promoted published value

  • Maximum screen voltage

    400 V

    Promoted published value

  • Maximum plate dissipation

    35 W

    Promoted published value

  • Maximum screen dissipation

    6 W

    Promoted published value

  • Maximum cathode current

    175 mA

    Promoted published value

  • Voltage (AC or DC)

    0.6 V

    Heater Characteristics and Ratings (Design-Center YaluesJ:

  • Current at heater volts =

    600 V

    Heater Characteristics and Ratings (Design-Center YaluesJ:

  • respect to cathode

    300 V

    Heater Characteristics and Ratings (Design-Center YaluesJ:

  • respect to cathode

    200 V

    Heater Characteristics and Ratings (Design-Center YaluesJ:

  • Plate `Joltage

    400 V

    Characteristics, Class A l AmOl ifier:

  • Grid-No.2 Voltage

    225 V

    Characteristics, Class A l AmOl ifier:

  • Grid-No.1 Voltage

    -16.5 V

    Characteristics, Class A l AmOl ifier:

  • Plate Resistance (Approx )

    27000 ohm

    Characteristics, Class A l AmOl ifier:

  • Transconductance

    9000 uS

    Characteristics, Class A l AmOl ifier:

  • Plate Current

    87 mA

    Characteristics, Class A l AmOl ifier:

  • Grid-No.2 Current

    4 mA

    Characteristics, Class A l AmOl ifier:

  • for plate ma. =

    35 V

    Characteristics, Class A l AmOl ifier:

  • PLATE VOLTAGE.

    600 V

    Maximum Ratings, Design-Center Values:

  • GRID-No.2 (SCREEN-GRID) VOLTAGE

    400 V

    Maximum Ratings, Design-Center Values:

  • CATHODE CURRENT

    175 mA

    Maximum Ratings, Design-Center Values:

  • GRID-No.2 INPUT

    6 W

    Maximum Ratings, Design-Center Values:

  • PLATE DISSIPATION

    35 W

    Maximum Ratings, Design-Center Values:

  • Plate Voltage

    400 V

    Typical Operation and Characteristics:

Characteristic

  • Plate resistance

    12000 ohm

    Promoted published value

  • Transconductance

    11000 uS

    Promoted published value

Data set 04

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Beam Power

Other

  • Grid No.l to plate

    0.85 pF

    Other

  • For fixed-bias operation

    0.05 megohm

    MaximumCircuitValues

  • For cathode-bias operation

    0.25 megohm

    MaximumCircuitValues

  • Plate Voltage

    600 V

    MaximumRatings

  • Grid-No. 2

    400 V

    MaximumRatings

  • Negative-bias value

    300 V

    MaximumRatings

  • Positive-bias value

    0 V

    MaximumRatings

  • Cathode Current

    175 mA

    MaximumRatings

  • Grid-No.2 Input

    6 W

    MaximumRatings

  • Plate Dissipation

    35 W

    MaximumRatings

  • Plate Voltage

    250 V

    TypicalOperation;PublishedValue1

  • Plate Voltage

    400 V

    TypicalOperation;PublishedValue2

  • Grid-No.2 Voltage

    250 V

    TypicalOperation;PublishedValue1

  • Grid-No.2 Voltage

    225 V

    TypicalOperation;PublishedValue2

  • Grid-No.l Voltage

    -14 V

    TypicalOperation;PublishedValue1

  • Grid-No.l Voltage

    -16.5 V

    TypicalOperation;PublishedValue2

  • Peak AF Grid-No.l Voltage

    14 V

    TypicalOperation;PublishedValue1

  • Peak AF Grid-No.l Voltage

    16.5 V

    TypicalOperation;PublishedValue2

  • Zero-Signal Plate Current

    140 mA

    TypicalOperation;PublishedValue1

  • Zero-Signal Plate Current

    87 mA

    TypicalOperation;PublishedValue2

  • Max. -Signal Plate Current

    150 mA

    TypicalOperation;PublishedValue1

  • Max. -Signal Plate Current

    105 mA

    TypicalOperation;PublishedValue2

  • Zero-Signal Grid-No.2 Current

    12 mA

    TypicalOperation;PublishedValue1

  • Zero-Signal Grid-No.2 Current

    4 mA

    TypicalOperation;PublishedValue2

  • Max. -Signal Grid-No.2 Current

    28 mA

    TypicalOperation;PublishedValue1

  • Max. -Signal Grid-No.2 Current

    18 mA

    TypicalOperation;PublishedValue2

Data set 05

2026 JJ Electronic

Published operating points and test conditions from this source.

SECTION 1

Beam Power

Other

  • Uf

    6.3 V

    Published value

  • If

    1.6 A

    Published value

  • Ug1

    -300 V

    Published value

Characteristics

  • Ua

    250 V

    Published value

  • Ug2

    250 V

    Published value

  • Ug1

    -14 V

    Published value

  • Ia

    140 mA

    Published value

  • Ig2

    12 mA

    Published value

  • S

    11800 µS

    Published value

Capacitance

  • cg1

    14 pF

    Published value

  • ca

    12 pF

    Published value

  • ca/g1

    0.85 pF

    Published value

Data set 06

2026 Sovtek

Published operating points and test conditions from this source.

SECTION 1

Beam Power

Other

  • Power Output

    20 W

    Plate 400 V; Screen 225 V; ClassA;TetrodeConnection

Data set 07

2026 Tungsol Rebrand

Published operating points and test conditions from this source.

SECTION 1

Beam Power

Other

  • Power Output

    -

    HI-FI audio power output