Hello, This http://www.ebay.com/itm/112324437388?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT one is working fine, I asked the seller, and he told me this module sw frequency are 1.2MHz. I also used a 800mAh Li cell, http://www.ebay.com/itm/111832711745?_trksid=p2057872.m2749.l2649...