The HB9CV-Beam is a 2-Element-Yagi with two driven elements and was introduced by Rudolf Baumgartner, HB9CV, in the 1950ies. It is astonishing that this antenna is not well known in many countries despite its gain of about 4,1-4,2dBd.
The app calculates the dimensions of the HB9CV antenna for any frequency or band which allows ambitious ham radio amateurs to build his own antenna. Dr Andreas Falkenberg (AI6HD) is a ham radio amateur himself while at the same time provides software development services. With this new App Dr Falkenberg enters both the amateur radio market and the Apple app market.