[unit91]

That's the antenna trimmer screw.  It usually winds up being screwed in clockwise almost all the way for best reception.  Make sure you have a good antenna connection.  The screw is adjusted by finding a weak station around 1400 and adjusting to maximum volume.  Your radio, however, may be on the fritz.

Craig R

I checked my stereo AM stations (on my old Pioneer SX-828 receiver from the 70s) to find a station around 1400.  Found one at about 1430, but can't get anything on the Ford radio.  Do you repair these?