GB1102116A - Apparatus for recording respiratory murmurs - Google Patents

Abstract

1,102,116. Apparatus for recording respiratory murmurs. VSESOJUZNY NAUCHNOISSLEDOVATELSKY INSTITUT RADIOVESCHATELNOGO PRIEMA IAKUSTIKI IM POPOVA. 29 March, 1966, No. 13830/66. Heading A5K. [Also in Division H4] An apparatus for recording respiratory murmurs is illustrated with reference to the drawing and includes a transducer, such as microphone 6, arranged to be applied to the chest of a patient and connected to an amplifying channel 7, wherein the amplifying channel is provided with a number of filters arranged to divide the frequency range of the murmurs into a number of different frequency bands, such as 1, 2, 3, 4 and 5 in the drawing, each of which is arranged to 'be recorded simultaneously on a separate channel of a recording instrument 25, the overall frequency range covered being between 125 and 6,000 cycles per second. A phonocardiagram may be recorded on a further channel of the apparatus, e.g. by microphone 26 and amplifying unit 27, and a pneumogram may be recorded on another channel, e.g. by use of closed chamber 28, capacitive transducer 29 and amplifier 30. In the drawing, the filter 11 has a pass band of 125-250 cps, filter 14 of 250-500 cps, filter 17 of 500-750 cps, filter 21 of 750-2,000 cps, and filter 23 of 2,000 to 6,000 cps.