When using nor gates only do I use the SOP, double bar it, and then change all the ands to an or? Or do i use the pos and double bar that then use demorgans?

my first attempt was,
F=A'BC'D' + A'B'C'D + ABC + AB'C --> need to use nor gates only for this

F = (A + B' + C + D' + A + A' + B' + D + A' + B + C)'

it looks weird to me =/
you cant simply if the whole thing is bar, can you?

any help would be appreciated
thanks

 

nvm i figured out what i did wrong

 

Glad you figured it out. You might be interested in one of my blog posts related to this:

http://forum.allaboutcircuits.com/blog/boolean-logic-sop-and-pos-forms.583/