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Power - Triode (over 1000V 100W) ·Triode

3CX300A1

Low-mu ceramic/metal power triode developed specifically for high-quality audio amplification. Suitable for single-ended Class A1 or push-pull A1/AB1 operation, with published outputs of about 15 W single-ended and 40 W push-pull.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
SK2A
Base pins
-
Nominal heater
6.3 V / 2.65 A

Description

High-power triode, metal-ceramic construction, external anode with 300-watt

Socket description

Svetlana SK2A 8-contact ceramic transmitting-tube socket family

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
SK2A
Base pins
-
Nominal heater voltage
6.3 V
Nominal heater current
2.65 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

Triode

X-ray radiationInterelectrode capacitances
Amplification factor
9
Max plate voltage
1800 V
Max plate dissipation
300 W
Max grid dissipation
1 W
Max cathode current
470 mA

Published ratings/characteristics promoted where unambiguous.

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

199X Svetlana

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Current

    2.65 A

    3CX300A1 is suitable for single-ended Class A1 or push-pull Class A1 or AB1 operation.

  • Plate resistance

    450 ohms

    3CX300A1 is suitable for single-ended Class A1 or push-pull Class A1 or AB1 operation.

  • Input

    25 pF

    3CX300A1 is suitable for single-ended Class A1 or push-pull Class A1 or AB1 operation.

  • Output

    1 pF

    3CX300A1 is suitable for single-ended Class A1 or push-pull Class A1 or AB1 operation.

  • Feedback

    10 pF

    3CX300A1 is suitable for single-ended Class A1 or push-pull Class A1 or AB1 operation.

Other

  • DC plate voltage

    1800 V

    Maximum Ratings

  • Maximum signal DC plate current

    470 mA

    Maximum Ratings

  • Grid dissipation (maximum)

    1 W

    Maximum Ratings

  • Control grid maximum negative voltage

    -400 V

    Maximum Ratings

  • Plate voltage

    500 V

    Typical Operation, Class A, Audio Amplifier (single tube)

  • Grid voltage

    -55 V

    Typical Operation, Class A, Audio Amplifier (single tube)

  • Plate current, no signal

    80 mA

    Typical Operation, Class A, Audio Amplifier (single tube)

  • Plate current, max signal

    95 mA

    Typical Operation, Class A, Audio Amplifier (single tube)

  • Effective load resistance

    1600 ohms

    Typical Operation, Class A, Audio Amplifier (single tube)

  • Distortion at 1 watt into

    8 ohms

    Typical Operation, Class A, Audio Amplifier (single tube)

  • Power output at 5% distortion

    15 W

    Typical Operation, Class A, Audio Amplifier (single tube)

  • Plate voltage

    500 V

    Typical Operation, Class AB1, Audio Power Amplifier, Push-Pull

  • Grid voltage

    -45 V

    Typical Operation, Class AB1, Audio Power Amplifier, Push-Pull

  • Plate current, no signal (both tubes)

    300 mA

    Typical Operation, Class AB1, Audio Power Amplifier, Push-Pull

  • Load resistance, plate-to-plate

    2000 ohms

    Typical Operation, Class AB1, Audio Power Amplifier, Push-Pull

  • Power output

    40 W

    Typical Operation, Class AB1, Audio Power Amplifier, Push-Pull

  • obtain base temperature not more than

    220 ˚C

    Typical Operation, Class AB1, Audio Power Amplifier, Push-Pull