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Mobile Antenna Cutting and Tuning

In this video I demonstrate how to use a tracking generator with a return loss bridge to tune a mobile vhf 1/4 wave antenna mounted in a bad spot. Many heavy equipment antenna installs require a compromise in location and surrounding metal. The normal ideal antenna locations cannot be used because they are exposed to tree limbs that would rip them off, this rules out 1/2 wave antennas as well. You cannot rely on the chart when cutting the whip to the right length in these situations. It is very hard to do it using a watt meter. By slowly cutting 1/2" segments while tracking the change, the goal is to get center tuned on the biggest dip to cover your targeted frequency range. In this example I am trying to cover 150-160Mhz, with a return loss better than 9.6dB/1:2 VSWR over that range, with near metal objects and less than ideal ground plane.