[Chris W]

owch ... once the magic smoke is gone its too late the electronics won't work.

from an electronics tech perspective check the boards for cold solder joints. (dull grey lumps) a good solder joint will have a shine to it.

also the other bane is flux that has not been cleaned off the board, more of a problem for higher voltage applications but will also mess with frequency circuits. if the board doesn't look clean or has a couple grey lumps get some alcohol from the drugstore, ask the pharmasist for the higher concentrated formulation (95% or so) they may ask just tell them its to clean electronic boards.

to fix the grey lumps use some wire braid and flux to pull away the solder (you'll need a 25-45 watt iron, don't use the big gun type. they have too much heat and are unwildy for precise work) the braid will absorb the molten solder. get best as you can and resolder the joint with some fresh rosin core solder. don't be afraid of using flux, it will make the solder flow better.

if you don't want to risk the electronics call a friend that has some experience or if the radio has lots of issues get a hold of the manufacturer for a replacement or re-work.

usually the low end electronics will have poor cleanup issues (i only found such in some audio equipment and a couple bass amps i picked up over the years) i only had to touch up one solder joint in my old attack 4 FM radio.

fly safe.