Transmitted disturbances

       

At a distance of about 30 cm from a fluorescent lighting tube with magnetic ballast and electronic starter, which is normally regarded as fairly electromagnetically compatible, this mains independent, battery powered thermometer was operated. It displayed the temperature flawlessly until – oops – somebody switched off the light at the wrong moment. It’s all no use – the battery has to be taken out and put back in: the only way to get the thermometer functioning again.