The question you ask is very broad.

I suggest you get a copy of any ARRL Radio Amateur's Handbook and
start there. If your interest is not high enough to pay the price of
the book, most Public Libraries have copies to loan. At this point,
the year of publication is not likely an important consideration.

After that, rephrase your question and come back to the group.

On 2 Sep 2005 18:21:07 -0700, wrote:

greetings,

can someone direct me on the ways driven element of a yagi is attached
to a boom. can a driven element (folded dipole or ordinary
dipole)electrically connected to a boom or not? what will be the
effect? or can i use wood as a boom? can someone also give me some
formula on yagi design (length, spacing etc)

help would be greatly appreciated.

thanks,

ian