First things, I do not understand toroids and I hope to change that someday. I need to make a switchable balun like the Elecraft BL2 Balun. It is switchable between 1:1 and 4:1 . In my junk box I have T50-6 toroids and T68-6. Is it possible to make 1:1 and 4:1 baluns with these toroids, if so how do I determine the number of winding's. It will be for QRP power levels only with no more than 10 watts for SSB.