Searching for UNUN?

antenna construction What is the purpose of a balun and a unun in a feed line? Amateur Radio Stack Exchange.
Amateur Radio beta. What is the purpose of a balun and a unun in a feed line? up vote 11 down vote favorite. I have never understood how a balun or a unun works and under which situation I need to use either of them in an antenna feed line.
Balun and Unun Configurations Palomar Engineers.
Balun and Unun Configurations. We often get the question Do I need a balun or an unun? The proper question is do I need a feed line choke or an impedance transformer whose output is configured as balanced balun or as unbalanced unun?
91: unun QRZ Forums.
Click to expand. Your unun looks good, and the windings and solder connections appear to be in the right place, but if any of the enamel coating wore or chipped off where the wires touched, it may be difficult to tell if there is a short with a visual inspection.
When to use an UNUN.
A unun is wound on a ferrite core and has special winding construction to make it useful over a wide range of RF frequencies, but it's' essentially just a transformer technically speaking, it's' typically an autotransformer, but you can get power autotransformers too.
9/1 UNUN ON7FU Ferrite Applications.
The feedpoint impedance of such a random wire length referred to ground varies widely, depending on the frequency used and the setup shape of the antenna. In order to transform the average feedpoint impedance of the antenna within the comfortable tuning range of an good a-symmetric antenna tuner, a 9/1 UNUN impedance transformer is often used.
Playing with end-fed wire antennas and 91: ununs KB6NU's' Ham Radio Blog.
Anyway, since my friend Rich, KA8BMA, had wound his 91: unun on a T106-2 core, I thought Id try this, too, and I just happened to have one in my box o toroids Well, wouldnt you know it, the measurements are much, much better with the T106-2 core than they were with the T80-2 core.The SWR measured 11: on 20m and 17m, something like 1.81: on 40m, and 1.51: on 15m. The frequency response of this unun isnt as flat as the unun wound on the ferrite core, but it is certainly much better than the unun wound on the T80 core.
Soil survey of Powell County Area, Montana Google Boeken.
19 inch Ppt 35 percent slopes area reclaim available water capacity Bignell blue huckleberry bluebunch wheatgrass CL-ML clay loam clayey common beargrass common juniper common snowberry cn Deep to water depth to rock Douglas-fir droughty elk sedge erodes easily Evaro excess fines Forestland frost action frost-free period Slope gravelly loam Grazeable Understory-Productivity green needlegrass heartleaf arnica Idaho fescue Improbable inch Ppt zone kinnikinnick Limited available water Lodgepole pine Low soil strength lupine Martinsdale Moderate Moderate northern Rocky Mountain d d percs slowly perennial forbs perennial grasses Perma pinegrass Ponderosa pine Poor Potential for ground-water prairie junegrass Rangeland and Grazeable Rock outcrop Rocky Mountain Normal rough fescue seepage serviceberry Short frost-free period shrinkswell Silty Slight Moderate Slope Large stones small stones Soil Name Subalpine Subalpine fir twinflower Understory-Productivity and Characteristic unun vovo west Unfavorable Western larch wetness white spirea Winfall Worock Yreka.
91: Magnetic Longwire Balun / Unun M0UKD Amateur Radio Blog.
Again, with a good ground, no choke will be necessary and the antenna can perform at its best. Keep the coax between the UnUn and tuner as short as possible. Ideally put the tuner next to the UnUn, or better still, use the tuner instead of the UnUn, at the feedpoint of the inverted V!

Contact Us