Jordstøj

Jordstøj, also known as ground noise or earth noise, refers to unwanted electrical signals that are present on an electrical ground or earth connection. This noise can originate from various sources, including electromagnetic interference (EMI) from external devices, currents flowing through the ground conductors due to imbalances or faults, and thermal noise within the conductors themselves. In electronic systems, a clean and stable ground connection is crucial for proper operation, as it serves as a reference point for voltage signals and helps to dissipate unwanted charges.

The presence of jordstøj can lead to a range of problems, such as corrupted data, reduced signal-to-noise ratios, and malfunction of sensitive electronic equipment. In audio systems, it can manifest as audible hum or buzz. In digital circuits, it can cause bit errors or timing issues. Mitigation strategies for jordstøj often involve careful grounding techniques, such as using star grounding or bonding to minimize ground loops, which are paths where different ground points are connected, allowing currents to flow and create voltage differences. Shielding of cables and equipment can also help to prevent external interference from entering the ground system. Proper filtering and decoupling at power supply entry points can also reduce the ingress of noise. In some cases, specialized isolation transformers or active ground conditioners may be employed to further improve the quality of the ground reference.