% Author: Dr. Matthias Jung, DL9MJ
% Year: 2020
\begin{tikzpicture}
    \def\slabels{{"~","1","~","3","~","5","~","7","~","9","~","+20","~","+40","~","+60~dB","~"}}
    \def\svalues{{-8,-7,-6,-5,-4,-3,-2,-1,0,1,2,3,4,5,6,7,8}}
    \def\swrvalues{{-3,-2,-1,0,1,2,3}}
    \def\swrlabels{{"1","1.5","2","3","~","~","$\mathrm{\infty}$"}}
    
    \def\centerarc[#1](#2)(#3:#4:#5)% Syntax: [draw options] (center) (initial angle:final angle:radius)
    { \draw[#1] ($(#2)+({#5*cos(#3)},{#5*sin(#3)})$) arc (#3:#4:#5); }

        % Beschneiden
        \clip[] (-6.2,7.5) rectangle (+5.8,1.55);

        % S-Meter:
        \foreach \b in {-7,-6,...,7}{
            \edef\c{90 - \b * 6.25}
            \pgfmathparse{Mod(\b,2)==0?1:0}
            \ifnum\pgfmathresult>0
                \pgfmathparse{\b<=1?1:0}
                \ifnum\pgfmathresult>0
                    \draw[thick] (\c:6.5) -- (\c:6.8);
                \else
                    \draw[thick, black!50] (\c:6.5) -- (\c:6.8);
                \fi
            \else
                \pgfmathparse{\b<=1?1:0}
                \ifnum\pgfmathresult>0
                    \draw[ultra thick] (\c:6.5) -- (\c:6.8);
                \else
                    \draw[ultra thick, black!50] (\c:6.5) -- (\c:6.8);
                \fi
            \fi
        }

        \foreach \i in {0,1,...,16}{
            \edef\c{90 - \svalues[\i] * 6.25}
            \draw (\c:7.1) node[rotate=\c-90] {\footnotesize\pgfmathparse{\slabels[\i]}\pgfmathresult};
        }

        % Power:
        \foreach \b in {-50,-49,...,50}
            \edef\c{90 - \b * 1.0}
            \draw[] (\c:6.4) -- (\c:6.30);
        \foreach \b in {-50,-45,...,50}
            \edef\c{90 - \b * 1.0}
            \draw[] (\c:6.35) -- (\c:6.25);
        \foreach \b in {-50,-40,...,50}
            \edef\c{90 - \b * 1.0}
            \draw[] (\c:6.25) -- (\c:6.10);
        \foreach \b in {-50,-40,...,50}
            \edef\c{90 - \b * 1.0}
            \pgfmathtruncatemacro\result{abs((\b+50))}
            \draw (\c:5.9) node[rotate=\c-90] {\footnotesize\result};

        % SWR:
        \foreach \b in {-3,-2,-1,0,1,2,3} {
            \edef\c{90 - \b * 16.666}
            \draw[] (\c:5.6) -- (\c:5.40);
        }

        \foreach \i in {0,1,2,3,4,5,6} {
            \edef\c{90 - \swrvalues[\i] * 16.666}
            \draw (\c:5.2) node[rotate=\c-90]{\footnotesize\pgfmathparse{\swrlabels[\i]}\pgfmathresult};
        }


        % Kreisboegen:
        \centerarc[ultra thick, black!50](0,0)(82.5:40:6.5)
        \centerarc[ultra thick](0,0)(140:83.5:6.5)

        \centerarc[thick](0,0)(140:40.0:6.4)

        \centerarc[thick](0,0)(140:40.0:5.6)

        \centerarc[thick, double distance = 0.2cm, line cap=rect](0,0)(139:80.0:4.7)
        \centerarc[thick, line width=0.2cm, line cap=rect, black!50](0,0)(139:120.0:4.7)

        % Beschriftung: 
        \edef\c{90 + 3.200 * 16.666} \draw (\c:4.7) node[rotate=\c-90, anchor=east]{\footnotesize ALC};
        \edef\c{90 + 3.150 * 16.666} \draw (\c:5.4) node[rotate=\c-90, anchor=east]{\footnotesize SWR};
        \edef\c{90 + 3.100 * 16.666} \draw (\c:6.1) node[rotate=\c-90, anchor=east]{\footnotesize PWR};
        \edef\c{90 + 3.050 * 16.666} \draw (\c:6.8) node[rotate=\c-90, anchor=east]{\footnotesize S};

        % Zeiger:
        %\draw[thick] (0,0) -- (+2.25,6.5); %+20
        \draw[thick] (0,0) -- (-2.25,6.5); %5
        %\draw[thick] (0,0) -- (0.75,6.9); %9

    \end{tikzpicture}