Both stations operate with 100,000 Watts Effective Radiated Power, however 99.1 is a Class C0 station, which allows them to operate at an antenna height over twice as tall as KFTK.
Also, KFTK is stuck about 25 Miles away from the master tower due to the fact that the Intermediate Frequency (IF) creates a harmonic that would interfere with KSLZ. Because of the fact that 107.7 is 97.1's IF frequency, reception of 97.1 can be a problem especially in South County and Illinois.
97.1 puts its best coverage North and West of St. Louis - in the "Westplex" area, as well as in North and West St. Louis County, 97.1 and 99.1 are on par with one another on signal level, and 97.1 travels into growing Lincoln and Warren counties with a better building penetrating signal than 99.1.
On the Maps, Grey would indicate a "City Grade" signal of over 70 dBu, Blue would be a good listenable signal, but reception in buildings could be somewhat of a challenge without a good radio (40-70 dBu), and areas in red would only be audible on a good car radio.
