diff --git a/contents/drawings/850.svg b/contents/drawings/850.svg index ff974f9..1d3ce3e 100644 --- a/contents/drawings/850.svg +++ b/contents/drawings/850.svg @@ -1,64 +1,88 @@ - + - - + + - - + + - - + + - - + + - - + + - - + + - - + + - - + + - - + + + + + + + + + + + + + + - - - + + - - - - - + + + + - - + + - - + + + + - - + + - - + + - - + + - - + + - - + + + + + + + + + + + + + + diff --git a/contents/drawings/850.tex b/contents/drawings/850.tex index ae57885..4c46e41 100644 --- a/contents/drawings/850.tex +++ b/contents/drawings/850.tex @@ -1,14 +1,46 @@ -% DL9MJ, Matthias Jung, 2024 -% Parabolspiegel -\begin{tikzpicture}[use optics] - \node[spherical mirror, spherical mirror angle=180, spherical mirror orientation=rtl] (M) at (0,0) {}; - \node[bareantenna, scale=0.25, anchor=left] (ant) at (M.focus) {}; - \draw (ant) -- (ant|-M.200) coordinate(h) -- (h-|M.280) coordinate (h) -- (h|-M.280) coordinate(trx); - \node[trxshape, scale=0.5, anchor=150] at (trx) {}; - \draw[DARCred] (M.focus) -- (M.170) -- (M.170-|M.0); - \draw[DARCred] (M.focus) -- (M.190) -- (M.190-|M.0); - \draw[DARCred] (M.focus) -- (M.150) -- (M.150-|M.0); - \draw[DARCred] (M.focus) -- (M.210) -- (M.210-|M.0); - \draw[DARCred] (M.focus) -- (M.130) -- (M.130-|M.0); - \draw[DARCred] (M.focus) -- (M.230) -- (M.230-|M.0); +% DL9MJ, Matthias Jung, 2026 +\begin{tikzpicture} + + % Parameter + \pgfmathsetmacro{\f}{1.4} % Brennweite + \pgfmathsetmacro{\ap}{2.4} % halbe Apertur + \pgfmathsetmacro{\xend}{5.0} % Ende der reflektierten Strahlen + + % Brennpunkt + \coordinate (F) at (\f,0); + + % Parabolspiegel: y^2 = 4 f x + \draw[ultra thick] + plot[ + variable=\t, + domain=-\ap:\ap, + samples=100, + smooth + ] + ({\t*\t/(4*\f)},{\t}); + + \draw({(-\ap)*(-\ap)/(4*\f)},{-\ap}) coordinate(end); + + % Feed / Antenne im Brennpunkt + \node[bareantenna, scale=1.0, anchor=west] (ant) at (F) {}; + + \draw(end) to [open] ++(2,0) node[trxshape, scale=1, anchor=west](trx){}; + + % Anschlussleitung und TRX + \draw (ant) + -- ++(0,-1.2) coordinate(h) + -| (trx.north); + + % Strahlen vom Brennpunkt zum Spiegel und danach parallel + \foreach \yy in {-2.0,-1.2,-0.4,0.4,1.2,2.0} { + \pgfmathsetmacro{\xx}{\yy*\yy/(4*\f)} + + % vom Brennpunkt zum Spiegel + \draw[DARCred, thick] + (F) -- (\xx,\yy); + + % reflektierter Strahl parallel zur Achse + \draw[DARCred, thick] + (\xx,\yy) -- (\xend,\yy); + } \end{tikzpicture} \ No newline at end of file