Bruel & Kjaer 1047 applications
https://testequipmentconnection.com/specs/Bruel_Kjaer_1047.PDF
https://www.technicalaudio.com/pdf/Bruel&Kjaer/Bruel&Kjaer_Signal_Generators_5596_5685_5716+WH-0255_5747_5827_1047+WH-0468.pdf
http://shura.shu.ac.uk/19492/1/10694373.pdf
https://scholarworks.rit.edu/cgi/viewcontent.cgi?article=1273&context=theses
