Beltone "Etude" Behind-the-Ear Hearing Aid The Beltone "Etude" behind-the-ear hearing aid was produced by the Beltone Electronics Corp. of Chicago, IL in 1972. This hearing aid used 8 transistors in an integrated circuit and a push-pull (PP) amplifier. The forward-facing microphone port is in the clear plastic above the ear hook. This aid used a ceramic microphone. The "Etude" could be fitted with an optional t-coil. |