[KA8VIT]’s build will be familiar to any air cannon aficionado. Built from 2″ Schedule 40 PVC, the reservoir is connected to the short barrel by a quarter-turn ball valve. Charging is accomplished through a Schrader valve with a cheap little tire inflator, and the projectile is a tennis ball weighted with a handful of pennies stuffed through a slit. Lofting an antenna with this rig is as simple as attaching a fishing line to the ball and using that to pull successively larger lines until you can pull the antenna itself. [KA8VIT] could only muster about 55 PSI and a 70′ throw for the first attempt shown below, but a later attempt with a bigger compressor got him over 100 feet. We’d guess that a bigger ball valve might get even more bang for the buck by dumping as much air as quickly as possible into the chamber.
Amateur radio is an eclectic hobby, to say the least. RF propagation, electrical engineering, antenna theory – those are the basics for the Ham skillset. But pneumatics? Even that could come in handy for hanging up antennas, which is what this compressed-air cannon is designed to do.
via Blog – Hackaday http://ift.tt/2ee5kMV