04796288 is referenced by 16 patents and cites 10 patents.

A telephone handset with static discharge prevention has a dielectric membrane extending over the metal ferrule of the transmitter, the membrane spaced from the ferrule by an annular dielectric spacer. At the receiver, a metal shunt on the front of the receiver has a central aperture for acoustic access. An annular dielectric membrane is positioned in the aperture and a dielectric membrane extends over the aperture, dielectric member and shunt. The membrane has a small hole within the annular dielectric member. The dielectric membrane at the transmitter increases the breakdown voltage to a value which will avoid static discharge to the user. The dielectric membrane and dielectric spacer at the receiver forms a long and sinuous discharge path which raises the breakdown voltage to a value which also avoids static discharge to a user.

Title
Telephone handset with static discharge prevention
Application Number
6/877569
Publication Number
4796288
Application Date
June 23, 1986
Publication Date
January 3, 1989
Inventor
Ronald G Wellard
Gloucester
CA
Josef Talacek
Don Mills
CA
Alan C Busche
Dorchester
CA
Agent
Sidney T Jelly
Assignee
Northern Telecom
CA
IPC
H04M 1/04
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