As posted . . ..  some reading for you . . .

First thread:

http://talk.newagtalk.com/forums/thread-view.asp?tid=136194&posts=11#M965277

Second thread:

http://talk.newagtalk.com/forums/thread-view.asp?tid=135779&posts=2#M961747

and there are others . . . .

Kind of spendy, but maybe the know off one is worthy of consideration . . . .