Radio frequency interference

Radio users, often amateur radio operators, report broadband noise on one or more bands, audible noise on receivers, or poorer reception. The noise may show up on several antennas. Interference alone does not prove the inverter is the source. Cabling, grounding, antenna systems, connectors or other electronics nearby can also cause it. First check which bands are affected and whether the noise happens by day, at night or both. Also check whether it follows inverter operation or PV production. If the noise starts at inverter power-up, changes with output power and stops when production stops, the PV system is likely involved. If it stays while the inverter is inactive, look for another source. Take wideband SDR or spectrum analyzer captures before and after inverter startup to see the affected frequencies and the noise pattern. Measure the noise at different distances from the inverter, the AC and DC cabling and the communication cables to find the emitter. Moving the antenna for a short time shows whether local coupling is the cause. Typical fixes are ferrite cores on AC, DC and communication cables, mains EMC filters, moving the antenna and putting more distance between the device and the receiver. If these give no measurable improvement, investigate further. Look at the whole system, including antennas, cable routing, grounding, connectors and communication wiring, rather than one component.

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• sentence 1: support check: partial - Symptoms are listed and amateur radio operators are mentioned, but 'often' amateur operators isn't stated (passage says amateur or other radio users).
• sentence 4: support check: partial - The observation list is given, but the interpretation (PV system likely involved vs. look for another source) is not explicitly stated.
• sentence 7: support check: partial - Ferrites, mains filters, repositioning antenna and increasing distance appear, but ferrites/filters were customer-tried tests, not stated as recommended fixes, and 'investigate further' is supported only loosely.
• sentence 1: review: partial - The symptoms and the multiple antennas are stated, but the passage says 'amateur radio operators or other radio users', not that the reports are often from amateur operators.
• sentence 4: review: partial - The passage lists the time-correlation observations, but does not state the conclusions (PV system likely involved, or look for another source). -->