240V MAINS POWER IS DANGEROUS AND CAN KILL
Some articles, case studies or posts may talk about the need to filter your main power supply. Some projects (kits or equipment maintenance) you consider may involve mains power.
There are mains filter circuits and kits available online and some may be referenced on ARTS and QRM Guru pages or external links.
ARTS, QRM Guru and its developers (and RASA) advise against any direct work with mains power where a licence (Electrical) is required. Mains power can kill.
For work involving mains power, the threshold of safety is reached when any type of tool-access is required. You can turn appliances off and on at normal, accessible switches, but never undertake any work that requires tools or access to a secure fitting or appliance. When considering mains filtering, amateurs may be able to attach commercial filters in-line or clip ferrites on the safe side of appliance cables, but when in doubt, discuss the work with a licenced electrician.
A suitable reference for enquiries relating to electrical safety is Energy Australia: