[mikethedruid]

You might also get a can of "freeze spray," fire up the radio, and wait until the radio craps out, then spray in little puffs on the Xtal,, and any associated circuitry, and see what happens. If the problem is temperature related, that is, if a component fails after it reaches a certain temperature, this can help track down the component. When it cools back down, it may well start working properly again. This will tell you which component is bad.