So, you think you know everything about ham radio, eh? Well have you ever heard about Near Vertical Incidence Skywave? Our own Dan Miller, KCØFRL has, and he’s going to be teaching us all about NVIS and NVIS antennas at this month’s general meeting. 7:00 pm is when it all starts, at the usual location: Plymouth Congregational Church.

Fine print for those don’t have a clue about what Dan will be talking about. Near Vertical Incidence Skywave, or NVIS, is a radio wave propagation method that provides usable signals in the range between groundwave and skywave distances (usually 30 to 400 miles, or 50 to 650 km). It is used mainly for military and paramilitary communications and by radio amateurs. The radio waves travel upwards into the ionosphere, where they are refracted back down and can be received within a circular region up to 650 km from the transmitter. If the frequency is too high, refraction fails to occur and if it is too low absorption reduces the signal strength. NVIS is most useful in areas where line-of-sight propagation at VHF or UHF frequencies is ineffective or when the communication distance is beyond ground wave (more than 50 miles) and less than sky-wave (300 to 1500 miles). More simply stated, NVIS communication is most effective for regional use. This may be used to handle emergency communication or simply for fun. There, now that you know the basics you’ll better understand what Dan’s going to be telling us and can come up with a couple of questions. Otherwise we’ll have to listen to Tre and Craig ask all the questions and you know how those lawyers like to talk….