In plain language: Find an RFI source by documenting the signature, narrowing time and location, removing suspected devices, and confirming the result with a repeatable on/off test.
Why an operator notices it
A noisy waterfall can look convincing while several unrelated sources overlap. The goal is not to guess what the trace resembles; it is to make one source disappear and return on demand.
Decisions that matter
- Record frequency span, time, antenna, receiver settings, and location.
- Use a portable receiver or near-field probe only as a direction-finding aid.
- Coordinate safely before switching household or site circuits.
A useful field check
- Run the receiver from battery if safe to separate utility-powered sources.
- Turn devices or circuits off one at a time.
- Confirm from more than one position before assigning blame outside the property.
Common wrong turns
- Accusing a neighbor from a single observation.
- Changing receiver gain between comparisons.
- Confusing normal digital emissions with harmful interference.
Technical foundation
This lesson translates established transmission-line and antenna practice into a field decision. Use the current equipment datasheet and Chameleon product guide for changing loss, power, connector, installation, and compatibility limits.
