Abstract: A keypad device for a mobile telephone or other device utilizing a keypad or keyboard is comprised of a flexible substrate and a keypad cover. The flexible substrate includes a plurality of keys affixed to the surface as well as a plurality first conductive strips associated with each key. The keypad cover is attached to the flexible substrate. The keypad cover typically includes holes that permit the plurality of keys to protrude through the keypad cover. In addition, the keypad cover further includes a plurality of second conductive strips that selectively contact a corresponding first conductive strip on the flexible substrate. The plurality of first conductive strips is coupled to ground and the plurality of second conductive strips is coupled to logic circuitry. Or, in another embodiment, both sets of conductive strips are coupled with the logic circuitry. The default position of the keypad device has each of the first conductive strips in contact with each of the corresponding second conductive strips.

Abstract: Existing automatic log on/log off systems in telephone systems determine whether or not a workstation is occupied, and that calls can be directed to that workstation, by determining whether or not the amplifier that provides the interface between the telephone system and the occupant's headset is plugged into the workstation. Recent headsets have a connector in the cord between the headset and the amplifier. This enables the occupant to leave the workstation without unplugging the amplifier, which defeats sensing mechanism of the existing automatic log on/log off system. An amplifier according to the invention replaces the existing amplifier and includes a detector that determines whether the headset is connected to the amplifier, and an activator that activates the existing automatic log on/log off system in the telephone system.

Abstract: A keypad monitor which monitors the condition of a plurality of switches of a keypad is activated in response to receiving clock signals from an external clock source and is deactivated in the absence of the clock signals. The keypad monitor includes a key switch monitor which detects the closure of any one of the keypad switches to provide a first output signal, a clock detector for detecting the absence of the clock signals to provide a second output signal and any key down output logic which is responsive to the first and second output signals for providing an activation signal. The activation signal causes the external clock source to provide the keypad monitor with the clock signals for activating the keypad monitor.

Abstract: Disclosed is a dialing apparatus used for a power failure extension telephone set 30 in a key telephone system. The power failure extension telephone set 30 is driven by power supplied from a key service unit 2 so as to function as an extension telephone set when power is supplied to the key service unit 2, but directly connected to an office telephone line 1 so as to function as an individual telephone set when power is not supplied to the key service unit 2. The dialing apparatus comprises a dial switch 31 of single contact-layer structure and a control switch circuit 21 connected to the dial switch 31 and changed over according to the power supply or power failure condition of the key service unit. That is, when power is supplied to the key service unit 2, the control switch circuit 21 connects the dial switch 31 to a control circuit 19.