Our battery mortar
At LZ Sharon, we had no American infantry support. Instead we had a quad-50 machine gun crew. A quad 50 is four 50 caliber machine guns mounted on the back of truck. The battery got a mortrar to shoot illumination rounds for the quad-50 crew to watch the perimeter. I ended up being the person primarily responsible for firing the mortar, perhaps because I was used to figuring up data for the artillery and could adjust the mortar fire pretty much in my head. We did not fire often, but we did occasionally. When we did, we would have to clear a whole grid square (a square kilometer) with the political clearance people to make sure that what we saw was not some friendly South Vietnamese blundering around where they should not be.