Comparisons between the model radio LCs from the 20 M_⊙ model and the observed radio LCs of SNe IIb 2001ig (Ryder et al. 2004) and 2003bg (Soderberg et al. 2006). The frequencies of the observed radio LCs are 2.4 GHz (square), 4.8 GHz (circle), and 8.6 GHz (triangle) in the left panel. The LCs of 2.4 GHz and 8.6 GHz are multiplied by 100 and 0.01, respectively, for illustrative purpose. In the right panel, the frequencies of the observed radio LCs are 8.46 GHz (square), 15.0 GHz (circle), and 22.5 GHz (triangle). The LCs of 8.46 GHz and 22.5 GHz are multiplied by 10 and 0.1, respectively. The radio LCs of SN 2003bg are multiplied by 0.2 as well to match the synthesized LCs.