🚀 go-pugleaf

Go to an electronics hobbyist shop and look for an "FM wireless mike"
kit or assembled unit.  If the circuit does not have provision for tuning,
you can try spreading or compressing the turns of the small coil to change
the frequency.  If you find you need additional range, increase the length
of the antenna.

If we were talking about jamming a TV signal, three Schottky inverters
in series makes a decent transmitter.