hi, Arthur:

Thanks, I also found the following link at
http://home.earthlink.net/~michaelpk...tenna_Mast.htm which has
instruction in details.

I have problems to open the "special nut". It said it will be much easier
to use special antenna nut wrench. I don't won't to spend money to buy
this special wrench. Any other good ideas to open the nut?

thanks,
mike