A simple project

I like it and would like to build one. Low PF caps can be harder to find laying around than the transistor or copper wire for the coil, so maybe twisted pairs of wire could be used to substitute for the small caps.

A minimal circuit like this one makes a good starting point for improvements...

I would try to add a crystal to lock the frequency, a pre-emphasis network to fix the sound quality, and a 2nd stage to control the power to the antenna.

Maybe a regulated power supply.

Of course an output filter to kill harmonics.

Your turn.