Hearing range 60 decibels, the hearing range for the Senegal bushbaby is 92 Hz–65 kHz, and 67 Hz–58 kHz for the ring-tailed lemur. Of 19 primates tested, the Japanese macaque had the widest range, 28 Hz–34.5 kHz, compared with 31 Hz–17.6 kHz for humans. Cats have excellent hearing and can detect an extremely broad range of frequencies. They can hear higher-pitched sounds than humans or most dogs, detecting frequencies from 55 Hz up to 79 kHz. Cats do not use this ability to hear ultrasound for communication but it is probably important in hunting, since many species of rodents make ultrasonic calls.
Aspidistra (transmitter) seven bomb-free zones in central and southern Germany. All these announcements were false. German radio stations tried announcing "The enemy is broadcasting counterfeit instructions on our frequencies. Do not be misled by them. Here is an official announcement of the Reich authority." However, "Aspidistra" broadcasts included similar announcements, leaving the listeners confused. Although mainly intended for the military and propaganda transmissions described above, "Aspidistra" was also used during the war for some BBC European Service broadcasts to Europe on 804 kHz. After 1945, "Aspidistra" continued to be used by the BBC. Frequencies used included 1122 kHz (1945–1950), 1340 kHz (1950–1962),