The Big Read: A sound method of time travel

My wife spent the last two weeks trying to fix an old radio. She opened it up and jiggled it and fiddled with things, and she tried my patented repair-technique of giving it a few hard shakes and then blowing vaguely but with intent in the general direction of the circuitry. She took it to four different repair places but this is Cape Town, where the providers of professional services are unstinting and unyielding in their efforts to avoid doing anything for which they might accidentally be pa...