Whistler (radio)A whistler is a very low frequency (VLF) electromagnetic (radio) wave generated by lightning. Frequencies of terrestrial whistlers are 1 kHz to 30 kHz, with maximum frequencies usually at 3 kHz to 5 kHz. Although they are electromagnetic waves, they occur at audio frequencies, and can be converted to audio using a suitable receiver. They are produced by lightning strikes (mostly intracloud and return-path) where the impulse travels along the Earth's magnetic field lines from one hemisphere to the other.
Campaign financeCampaign finance, also known as election finance or political donations, refers to the funds raised to promote candidates, political parties, or policy initiatives and referendums. Political parties, charitable organizations, and political action committees (in the United States) are vehicles used for fundraising for political purposes. "Political finance" is also popular terminology, and is used internationally for its comprehensiveness. Political donations to funds received by political parties from private sources for general administrative purposes.