I am living in a state where there is lots of Electricity cut off in other words the Loadshedding.When I listen to radio on short wave and medium wave during no electricity ON in our town, it plays well and clear. But when electricity comes its totally inaudible because of too much noise like srrrrrrr, shrrrrrrr,trrrrrrrr. Means I have to turn my radio off. My question is what thing does this cause??
Some electrical item in your house or close by is radiating EMI (Electromagnetic Interference). The frequencies of this EMI are the same as the radio broadcasts but much stronger - swamping them. Hence you just here the noises you do. You should try switching off your electrical items one by one to identify the culprit. If it is not an item in your house, then there's probably not much you can do.
It is interference produced by electrical equipment such as motors, TVs, transformers, computers and fluorescent lamps. I guess your radio is battery operated. If you take it a mile or so outside the town, you will find you get good reception with no noises. I get this at home too. I find if I want to listen to short wave, I need to turn everything off, including fridge, TV and computer. You could try turning everything off in your house and see if it helps.
