Authored by:
Basu (VU2NSB)
on February 28, 2020.
Does Low SWR always mean a good Antenna setup? Many amateur radio operators often assume it to be true but the question is, will low SWR always ensure that the antenna has been optimally setup? Although a low SWR on the transmission line to the antenna is certainly welcome, the question still remains whether it conclusively indicates a healthy antenna system setup? contrary to popular belief, No, not always… There are various other factors that go a long way in determining optimum antenna performance. This is notwithstanding the fact that the location of antenna installation, its surroundings, and height above ground play vital roles. Let us ignore these limiting factors because I know that most of us, the radio amateurs, are often constrained by real-estate limitations and therefore may not always be able to install our antennas the way we might have liked to. Within the realms of the above-cited limitations, the SWR is still not the ultimate indicator of antenna system health. Let us examine why is it so, and what are the other factors that could overshadow the...
Click Here to Read Full Article […]
Authored by:
Basu (VU2NSB)
on February 16, 2020.
Coaxial cable choke and RF common-mode noise Is it really true that a section of coiled coaxial cable choke at antenna feed-point would effectively cut down the radio RF noise substantially? Will the perceived reduction be enough to make operating especially on the lower frequency HF bands a pleasure? These are some of the questions that come to mind. Well, there are a multitude of opinions with many people suggesting that it is indeed worthwhile. Let us impassionately and realistically examine the effects of such coiled coaxial cable chokes that are often used near the antenna feed-point and figure out with rational scientific logic if they are truly as effective as one might be made to believe… At this point, some readers may feel impatient and say, stop beating about the bush, give us the bottom line… OK, the bottom line is NO! they don’t work well enough to feel jubilant or elated. Especially, on the lower HF bands like the 80m, or 40m. Even on the other higher frequency HF bands, they don’t perform as well as one might...
Click Here to Read Full Article […]