\documentstyle[ncs,12pt,qq]{article}
\font\cmr=cmr17
\font\svnncs=pncr at 17pt
\tracingmacros2
\begin{document}
\obeylines
\makeatletter
{\svnncs
Some characters: 
acute: \'{o} \'{e} \'{i} \'{u} \'{a}
grave: \`{o} \`{e} \`{i} \`{u} \`{a}
circum: \^{o} \^{e} \^{i} \^{u} \^{a}
dieresis: \"{o} \"{e} \"{i} \"{u} \"{a}
tilde: \~{o} \~{e} \~{i} \~{u} \~{a}
overbar: \={o} \={e} \={i} \={u} \={a}
dot: \.{o} \.{e} \.{i} \.{u} \.{a}
uthing: \u{o} \u{e} \u{i} \u{u} \u{a}
vthing: \v{o} \v{e} \v{i} \v{u} \v{a}
hungarumlaut: \H{o} \H{e} \H{i} \H{u} \H{a}
tie: \t{oo} \t{oe} \t{oi} \t{ou} \t{oa}
cedilla: \c{o} \c{e} \c{i} \c{u} \c{a} \c{c} \char24c
underdot: \d{o} \d{e} \d{i} \d{u} \d{a}
underbar: \b{o} \b{e} \b{i} \b{u} \b{a}
angstroms: \aa ngstrom \AA ngstrom \oa@ ngstrom \o@@ ngstrom
}
{\cmr
Some characters: 
acute: \'{o} \'{e} \'{i} \'{u} \'{a}
grave: \`{o} \`{e} \`{i} \`{u} \`{a}
circum: \^{o} \^{e} \^{i} \^{u} \^{a}
dieresis: \"{o} \"{e} \"{i} \"{u} \"{a}
tilde: \~{o} \~{e} \~{i} \~{u} \~{a}
overbar: \={o} \={e} \={i} \={u} \={a}
dot: \.{o} \.{e} \.{i} \.{u} \.{a}
uthing: \u{o} \u{e} \u{i} \u{u} \u{a}
vthing: \v{o} \v{e} \v{i} \v{u} \v{a}
hungarumlaut: \H{o} \H{e} \H{i} \H{u} \H{a}
tie: \t{oo} \t{oe} \t{oi} \t{ou} \t{oa}
cedilla: \c{o} \c{e} \c{i} \c{u} \c{a} \c{c} \char24c
underdot: \d{o} \d{e} \d{i} \d{u} \d{a}
underbar: \b{o} \b{e} \b{i} \b{u} \b{a}
angstroms: \aa ngstrom \AA ngstrom  \oa@ ngstrom \o@@ ngstrom
}
\end{document}
