ILE Exam Hearing Aids | 82 Questions and Answers.

ILE Exam Hearing Aids | 82 Questions and Answers. Hand Cupped Behind Ear - Correct answer--first Hearing Aid -increased sound by 5-8db -included horns,trumpets, speaking tubes 1892 - Correct answer--carbon amplifiers patent by Alexander Bell -marketed until 1930;first patent for a telephone type hearing instrument 1920 - Correct answer-large vacuum tubes; not portable 1938 - Correct answer-miniature vacuum tube ;crystal receivers 1930 - Correct answer-diameter reduced 1940 - Correct answer-bone conduction receivers were introduced 1946 - Correct answer-first telecoil introduced 1950 - Correct answer-bodyworn HA became convenient size 1948 - Correct answer-transistor invented 1954 - Correct answer-eyeglasses aids introduced 1974 - Correct answer-microphones electrets were introduced 1964 - Correct answer-intergrated circuit(transistors, resistors, wiring...) 1952 - Correct answer-first transistors The Most Important function of the oval window is to : - Correct answer-transfer vibration from the ossicular chain.