My own meager contribution would be to suggest that you sweep the frequency range from around 77kHz to around 800kHz (the parasite bandwidth). Repeated as a series of rising (and falling?) frequency pulses.
If you could hear this it would sound like a rising pitch police siren wailing up and down in frequency.
How easy it would be to do this? I don't know, but someone would point in the right direction I am sure.