Telephone hearing aid
First Claim
1. A telephone hearing aid for attachment to a telephone handset, the hearing aid having a disc shaped circular symmetric housing for an acousto-electric input transducer, an amplifier, a transformer having a primary winding connected in series with the input transducer and a secondary winding series connected to both an electro-acoustic output transducer and an electro-magnetic output transducer, said transducers being circular symmetric and concentrically located on the axis of the housing, said housing having a domed rear face adapted to fit into a dished face of the telephone handset receiver, and a resilient curved band extending from the housing and terminating at a self contained power source, said band enabling spring mounting of the telephone hearing aid onto a telephone handset with the telephone handset receiver gripped between said housing and said power source.
4 Assignments
0 Petitions
Accused Products
Abstract
A portable telephone hearing aid having an acousto-acoustic/magnetic amplifier providing a maximum gain of 20 dB has a circular housing at one end of a U-shaped resilient clip member for attaching it to the telephone receiver in a handset. A battery compartment, also housing an ON/OFF switch, and a gain control wheel, is located at the other end of the U-shaped clip.
72 Citations
12 Claims
- 1. A telephone hearing aid for attachment to a telephone handset, the hearing aid having a disc shaped circular symmetric housing for an acousto-electric input transducer, an amplifier, a transformer having a primary winding connected in series with the input transducer and a secondary winding series connected to both an electro-acoustic output transducer and an electro-magnetic output transducer, said transducers being circular symmetric and concentrically located on the axis of the housing, said housing having a domed rear face adapted to fit into a dished face of the telephone handset receiver, and a resilient curved band extending from the housing and terminating at a self contained power source, said band enabling spring mounting of the telephone hearing aid onto a telephone handset with the telephone handset receiver gripped between said housing and said power source.
Specification