[AlbertCory]

Wikipedia says he was using "pulses" instead of "continuous wave" which we now use. So maybe the question about "frequency" doesn't even apply? idk

[aidenn0]

Properly it was dampened waves. Pulses go into the antenna, but the antenna is resonant, so waves go out. A bit like hitting a tuning fork. Later on he used RLC resonant circuits for the same effect.