ELECTRONIC COMPONENTS & VALVES MOUNTED ON BOARD

The ECC82 (also known as 12AU7) is a dual triode vacuum tube widely used in audio amplification and radio frequency applications. It consists of two triodes in one glass envelope, each acting as an amplifying valve. Technical highlights include:

Heater Voltage: 6.3V or 12.6V depending on the configuration

Heater Current: 300 mA or 150 mA

Typical Anode (Plate) Voltage: 250V

Typical Anode Current: 10.5 mA

Amplification factor (μ): Around 17

Transconductance (S): Approximately 2.2 mA/V

Internal Resistance (Ri): About 7.7 kΩ

Maximum Anode Dissipation: 2.75 W

Base Type: Noval (9 pins)

Functionally, the ECC82 tube controls electron flow between the cathode and anode via a control grid, which varies the output signal amplitude. It is ideal for low-noise audio amplification, phase inversion, and driver stages in push-pull amplifier circuits. Due to its balanced and smooth sound output, it is popular in high-fidelity audio and guitar amplifiers. The tube is also known for low microphony, meaning it picks up little mechanical vibration noise.

The ECC82 is often mounted on circuit boards with associated passive components such as resistors and capacitors for filtering and biasing, integrating into practical audio and radio circuits.

This twin triode valve remains a classic component in vintage and modern electronics requiring smooth medium gain amplification with stable, low noise characteristics.

Triode valve (ECC 82) on board.