> The task is to measure the distance between two drive > units on a boat. The drives both propel and steer the boat. I'm having trouble picturing what this is. The phrase "drive unit" brings to mind an engine and transmission. Why would the distance between them change, aren't they bolted down? This is a serious question, I'm not kidding. Thanks, Bob -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist