Diode
Lad os "terpe" digital teknik. Dette diagram http://images.google.com/imgres?imgurl=ourworld.compuserve.com/homepages/g_knott/ttl.gif&imgrefurl=http://ourworld.compuserve.com/homepages/g_knott/elect352.htm&h=386&w=492&prev=/images%3Fq%3DTTL%26start%3D80%26svnum%3D10%26hl%3Dda%26lr%3D%26ie%3DUTF-8%26oe%3DUTF-8%26sa%3DN viser indgangende! A B C D men der er nogle små pile der pejer mod den vej strømmen vil løbe!Så kan den da ikke løbe eller hvad?
