74.1 Non-Math

<..text symbolsNO..>
 \def\AA{{\Protect\Tivht@AA}}
 \def\aa{{\Protect\Tivht@aa}}
 \def\Tivht@AA{%
    \ifx \EndPicture\:UnDef  \a:AA\else
      \leavevmode\setbox0\hbox{h}\dimen@\ht0\advance\dimen@-1ex%
      \rlap{\raise.67\dimen@\hbox{\char’27}}A\fi}
 \def\Tivht@aa{%
    \ifx \EndPicture\:UnDef  \HChar{229}\else \accent23a\fi }
 \NewConfigure{AA}{1}
 \Configure{AA}{\HChar{197}}
 -_-_-

A previous definition \def\aa{{\Protect\:aa}} was problematic because \:aa got into an aux file which got loaded with ‘:’ in catcode 13.

<..text symbolsNO..>+
 \def\vdots{\Picture+{ \a:@Picture{vdots}}
    \vbox{\baselineskip4\p@ \lineskiplimit\z@
     \kern6\p@\hbox{.}\hbox{.}\hbox{.}}\EndPicture}
 -_-_-