#Best elevation for slim jim hf antenna how to

In yet another scenario of a ground station antenna for LEO satellite use, one would expect an omnidirectional antenna to not only cover 360° in azimuth but also at all elevation angles above the surface of the ground thus producing a hemispherical dome-shaped radiation pattern above the earth.

For instance, for an antenna in free-space like an antenna onboard an LEO satellite, one might expect it to radiate uniformly in all directions in 3D space, whereas, for terrestrial HF station it would be expected to radiate uniformly in all directions (360°) around the azimuth (horizontal plane). However, in reality, the term Omnidirectional needs to be taken in the context of the communication application scenario. To understand more about band conditions and solar cycles CLICK HERE.In the literal sense, an Omnidirectional antenna is an antenna that radiates uniformly in all directions. Take charge of those solar cycles and choose one of the following Alpha Antenna systems that meets your operating objectives. We hope that you feel armed when taking what the band-conditions hand you. Other operators get one antenna, which can be deployed to either enhance DX or NVIS characteristics. Some operators get two antennas one for DX and one for NVIS. Losses are also higher where the home’s exterior walls have a chicken type wire under stucco or with aluminum siding. So placement on a balcony or in-front of the largest window after removing any metal screen will help if indoors. Performance in apartments can be significantly less in the direction through the building. You will typically see about 1.75 S-Unit of loss when operating inside a stick build home. Do not expect the same performance from an antenna indoor or antenna placed near a building as one that’s outside. Consider this when placing an antenna to enhance performance. The physical environment that surrounds antennas will have an impact on performance.

What the physical and environmental looks like where the antenna will be deployed.

Whether your target location requires NVIS or DX signal pattern,.

Antenna efficiency required to reach your target,.

How much interaction you would like with an antenna,.

What your own Physical limitations are,.

Determining factorsĬhoosing the best HF antenna for your physical and operational needs will determine whether you can successfully communicate or not. Just keep in mind if you do, that they will have a Signal Pattern similar to half of a dipole. These provide hands-free operation enabling you to just touch the button on your tuner when changing bands. Alternatively, you may choose to use one of our EFHW dipole antennas. The third most efficient antennas are the MIL 2.0 and the FMJ. Having a higher Q rating means an antenna has a narrower bandwidth. This is because they have a higher efficiency Q rating. These first two antennas are very effective for even low power operations. It requires you to turn a knob on the antenna to tune when changing bands. The smallest and second most efficient antenna is the magnetic Alpha Loop. This antenna requires you shorten or lengthen the Telescopic Elements with Tuning from one band to another. The most efficient and largest antenna is the HexTenna antenna. The FMJ, our HexTenna, and also the Alpha Loop all have the best HF antenna DX and NVS signal patterns. This is why our Alpha Antenna Loop, HexTenna, or EMCOMM systems are best when the horizons are obstructed. Conversely, a site that where horizons are not obstructed provide opportunity to directional signals to enhance DX. The trees, however, produce significant obstacles between a the antenna and the horizon.

This is because DX characteristics often rely on a low take-off angle to the horizon. This is because directly above the antenna the trees provide less of an obstacle, enabling NVIS to still propagate. We also know that the take off angles needed for DX is significantly impacted in the same heavily wooded areas. This is regardless of whether the antenna is placed in a relatively clear area or in a heavily wooded area. HF Antenna that exhibit primarily NVIS characteristics will work best for Regional Communications.

#Best elevation for slim jim hf antenna how to

How to choose the best HF Antenna for Portable, Mobile, or Base stations Whether your obstacles are trees, buildings, operating indoors, or something else HERE IS HOW TO choose an antenna that will work in your physical environment.