The followings are previous transponders that are not good anymore: 11874, 12060, 12090, 11789, 11836, 11867, 11808, 11997, 12022, 12177, 11912, 11998, 12029 and 11961 MHz.
The following are good transponders from my last Detailed Blind Scan: 11842, 11936, 11966, 12122, 12152, 11929, 12053...