Dear Sirs, I was just perusing your site and reading the page with the below link. I believe that you have got your NPN and PNP type the wrong way around. I think the best way to correct the page is to swap around references to the NPN & PNP on your page. I have checked with a meter and your diagrams where you are explaining how to check if a transistor is NPN or PNP , which is the base, emitter and collector, and whether they are faulty and my findings do not correspond with your explanations. Please be aware that in a multi meter the red prod is actually connected to the negative of the battery inside and the black prod is connected to the positive of the battery. Any problems with this please contact me <snip> The link for the page is: http://www.allaboutcircuits.com/vol_3/chpt_4/3.html. Regards & Thanks....Homayoun Behjat.