Hearing aid "AK-1".

Acoustic systems, passive or active, as well as electro-acoustic units, hearing aids, electric megaphones, intercoms ...Hearing AidsHearing aid "AK-1" (581M) was produced presumably since 1965 by the Moscow factory of hearing aids. It is used to compensate for small, large and medium hearing losses due to air or bone conduction. It can be powered by one or two batteries, which respectively provides a maximum acoustic gain of 60 and 128 dB. Has a smooth volume control and a four-stage tone control. The plant produced two models: AK-1V, equipped with an air conduction telephone, and the AK-1K model, equipped with a bone conduction telephone. The device is adapted for telephone conversations and excludes the influence of external noise. Dimensions of the device 66x44x15 mm, weight with two batteries 75 g. Presumably, since 1978, the plant has been producing a modernized apparatus "AK-1" (VM or KM), which is distinguished by the transfer of the circuit from germanium to silicon transistors and, accordingly, a more modern element base.