Periodic CT Signal
The first signal that comes to mind when i think of a periodic CT signal is one involving sines and cosines, so let's work with one of those.
Let $ x(t) = sin(14t)+(1+3j)cos(2t) $
This can also be expressed as
$ x(t) = \frac{e^{14jt}}{2j}-\frac{e^{-14jt}}{2j} + \frac{(1+3j)*e^{2jt}}{2} + \frac{(1+3j)e^{-2jt}}{2} $