The application of Reed-Solomon codes in slow frequency-hopped systems has been extensively studied. Earlier investigations assumed an infinite interleaving length and considered partial-band noise jammers only. This paper extends previous efforts by analyzing the effect of finite interleaving length and the impact of band multitone jammers. We also explain why two-threshold (2T) erasure-insertion methods (EIM) are needed and examine their performance. Numerical results are presented to compare the effectiveness of EIM's and jammer types and to study the relationships among the hop rate, the interleaver size, and the code rate. The use of 2T EIM's necessitates the estimation of several additional channel and signal parameters. Simple and effective estimation algorithms are provided as well.