I recently aquired a 1934 Westinghouse model WR-29 radio. it had been sitting in a basement for quite a long while before i got to it. the first thing i did when i got it home was to plug it in and turn it on, after it heated up it began to smoke slightly, so i turned it off and left it. upon trying to think of what could be the matter, i realized that i hadn't bothered to clean all of the dust and debris off of the chassis, could the possible cause be the heat from the tubes burning dust and dirt off? if not what else? what ought i to look for when inspecting the chassis?