Re: L/4 + Koaxradial
Verfasst: Do 10. Mär 2016, 11:39
Hab gerade zufällig noch was zum Koax-Radial gefunden (oder ist das was anderes?):
Scheint ja eine echte "Wunderwaffe" zu sein... Komischerweise erklärt aber keiner die Funktionsweise...
Hat vielleicht jemand das ARRL-Handbuch und kann mal einen Blick ins 11. Kapitel werfen?
Quelle: http://www.k0bg.com/match.htmlStub Matching
Any of the above matching schemes can be used to match a monoband antenna. However, there is another way that not only performs a conjugate match, but extends the bandwidth as well! Enter the shorted 1/4 wave stub! The drawback to this type of match is the fact is it monoband in nature. While you can cascade (parallel) stubs in some cases, the mechanical considerations become a headache. If nothing else, it is a lot less complicated than using an internal or external auto-coupler with about the same results.
Depending on a lot of factors not in evidence, the technique can extend the bandwidth by 2 or 3 times. The reason this is so, is the reactance curve of a 1/4 wave shorted stub vs. frequency is opposite that of the antenna. If you want to know more about how they work, Chapter 11 of the ARRL Handbook is the place to go.
Scheint ja eine echte "Wunderwaffe" zu sein... Komischerweise erklärt aber keiner die Funktionsweise...
Hat vielleicht jemand das ARRL-Handbuch und kann mal einen Blick ins 11. Kapitel werfen?