Sometimes you just don't have quite enough signal to access a repeater or communicate with another ham. One solution is to use a more effective antenna with a some gain and directivity. Of course you could purchase an antenna, but that can be rather expensive. You could also build one, but many believe there is too much math involved to determine all the element sizes and spacing. You should know that we can design an antenna to our own specifications, and it won't cost a bit. We can tweak the design based on parameters we want to consider: gain, SWR, front-to-back ratio, etc. Once designed we can then build it using some basic construction techniques.
A very powerful FREE application called 4NEC2 exists that greatly simplifies the antenna design process. 4NEC2 is a Windows-based application for creating, viewing, optimizing and checking 2D and 3D style antenna geometry structures. It can also generate, display and/or compare near/far-field radiation patterns for both the starting and experienced antenna modeler. 4NEC2 can be used to model and simulate just about any type of antenna from simple to complex. However, it is best to start out with a simpler antenna.
I propose a session (about 3 hours) during which I will demonstrate the basic design of a simple UHF Yagi-Uda antenna with 3 or 4 elements. We will input the initial parameters for the antenna and then watch as the application optimizes (tunes) it. At first glance the 4NEC2 app seems daunting and complicated, but we will only use some of the basic capabilities to design our antenna. The end result will be an antenna just about anyone would appreciate. Little, if any, additional tuning would be needed, and it could probably be put in operation just as it is designed.
If you are interested in attending such a session, please send us an email using the website's Contact Us menu selection and let us know you are interested. You can also email me at w9wrp@yahoo.com. With enough interest, I will schedule a session and keep you informed of the plans. We could probably have a session in July.
Note that a UHF Yagi has a pretty small footprint, and it could improve repeater access and reception if you are on the fringe. A 3-element antenna would likely have about 7dB of gain, and that might be all you need to allow use of your HT for more solid communications.
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