Many common appliances can cause interference to radio or television reception. A battery-operated portable AM radio can be used to locate electrical appliance interference in a household.
Step 1: Turn the radio on, select the AM band and check the identified offending interference can be heard. Normally, the interference will be heard across the AM band. Tune the radio so the interference can be clearly heard. This will generally be between radio stations.
Step 2: Hold the radio near the fuse box.
Step 3: While the interference is occurring, turn the mains power switch OFF. If the interference stops when the mains switch is operated, the interference is within the property. If the interference continues, then it’s coming from a source outside the property.
Step 4: Turn the mains power ON. The interference will generally return. If it does, individual electrical equipment in the property should be switched off until the interference stops, to identify the problem piece of equipment.