The Sony SRF-42 was Sony's entry-level AM Stereo "walkabout" unit. The photo above came from the box that the SRF-42 came in, so I cannot take credit for the photography. :-)
Despite the shirt-pocket size, the radio can do some amazing things. Its designed, of course, for AM Stereo reception, which means that when you tune across the AM band and run across a station using the Motorola C-QUAM system, the sound in your headphones "opens up" and you are treated to real AM stereo!
Now, a couple words about AM Stereo: it's not as rich-sounding as FM stereo, but seems to be light-years away from plain old AM. The issue is finding local stations who use the feature to its greatest advantage: here in Chicago, a couple of the news-talk stations use stereo, which means that the occasional commercial or sporting event comes through with a little more "space." I used to live near a station that broadcast music in AM stereo, so I took advantage of that fact before I moved.
Another negative about this set is that Sony put very little into the FM side of this radio. Reception on FM is just plain lousy, which is a real disappointment for a unit that was designed to be used specifically as a radio (as opposed to a radio/tape combination). There was an internet denizen who used to say that in general "Sony's FM sections rot." Frankly, given the splatter and clipping you hear on the band, I have to say that person is right in this case.
This unit sold in the $30 range from a number of sources, including Radio Shack, as late as 1999. I bought mine at Chicago's Sony Gallery in early '94, right about the time it was introduced. This may be a collector's item someday!