Hello

I put a low wattage light into a porch light which is on a 2 way switch.
Every 5 seconds the bulb flickered when the light was switched off
Does anyone have any idease why this might be happening

Thank you

I am guessing the lamp is a compact fluorescent type. Fluorescent lamps can be dimly illuminated by radio frequency transmission waves. Is there a radio/ TV transmitter nearby? Or a Ham Radio operator? I suspect there is some sort of RF in your neighbor hood to cause the light to flicker when the power is off.