Please refer to this link to see what I am working with. http://www.ebay.com/itm/150940992983?_trksid=p2057872.m2749.l2649&ssPageName=STRK:MEBIDX:IT I am wondering about combining the output of 2-4 of these mikes into one input. I assume I should not just have the white signal lines tied together. Is there a passive way to safely combine them rather than have to use a normal active mower? Thanks for thoughts and suggestions.