I worked at Motorola and adjusting the trimmer for the antenna at 1400 Kc was necessary for good performance. Different models had different tune up points. Some were 800 kc and a few down at 600 kc. Depended on what car model it was to be installed in and also if it was for Ford, Chevrolet, or Chrysler. A short FireStik might work really good for late night DX am.