Doctor Who, once new with jet power, possibly, and added energy (3,7)

'doctor who' is the definition.
I don't know anything about this answer so I can't tell whether this works.

'new with jet power possibly and added energy' is the wordplay.
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'with' is a charade indicator (letters next to each other).
'possibly' indicates an anagram.
'and' is a charade indicator (letters next to each other).
'added energy' becomes 'e' (physics symbol as in E=mc2. I am not sure about the 'added' bit.).
'jet'+'power'='jetpower'
'n' put after 'jetpower' is 'jetpowern'.
'jetpowern' anagrammed gives 'jonpertwe'.
'jonpertwe'+'e'='JON PERTWEE'

'once' acts as a link.

Can you help me to learn more?