Attenburrow D P
Equine Vet J. 1978 Jan;10(1):14-7. doi: 10.1111/j.2042-3306.1978.tb02206.x.
The development of a radio-stethoscope for horses is described. The equipment consisted of a sound transducer applied to the skin adjacent to the trachea and a radio transmitter attached to the saddle. The signals emitted were detected by telemetry and recorded on a magnetic tape-recorder. The recorder incorporated a monitor earphone so that sounds could be reproduced at the time of recording. The frequency response obtainable ranged from a few Hz to 4 KHz. This technique provided an objective means of studying the respiratory sounds generated during exercise although absolute values could not be measured.