Just a short clip of the lash up I'm using to get on 70CM in the ARRL UHF contest. The drive on mount is made of plumbing supplies. The light duty tv mast slips in, then gets folded in to an upright position, and secured to the truck by a bungee cord. The mast can only fold to vertical in one direction due to the stop built in to it. Total cost was about $20 in parts several years ago when I made it. The mast was a yard sale find for 50 cents a section.