|
US5381486A
|
|
Communications headset having a universal joint-mounted microphone boom
|
|
US5450496A
|
|
Communications headset having a detachable receiver capsule and cable pivot
|
|
US5260997A
|
|
Articulated headset
|
|
US5226077A
|
|
Headset amplifier with automatic log on/log off detection
|
|
US5353347A
|
|
Telephone headset amplifier with battery saver, receive line noise reduction, and click-free mute switching
|
|
US5070527A
|
|
Time dependant, variable amplitude threshold output circuit for frequency variant and frequency invarient signal discrimination
|
|
US4928307A
|
|
Time dependent, variable amplitude threshold output circuit for frequency variant and frequency invariant signal discrimination
|
|
WO8904106A1
|
|
Acoustic filter microphone cup
|
|
US4926961A
|
|
Hinged acoustical voice tube
|
|
US4864610A
|
|
Earpiece for a telephone headset
|
|
US4754484A
|
|
Convertible handset/headset for telephone
|
|
US4420657A
|
|
Adjustable headset
|
