Parallel off-hook detection for both line-available and...
Party intercept in selective multifrequency ringing systems
Party line converter
Party line privacy device
Party line telephone system employing and private trunk
Party-line telephone systems
Partyline subscriber interface circuit
Passivation of external keys of a communication device in a...
Passive distributed filter system and method
Passive information access system
Passive system used to merge telephony and broadband signals...
Passive telecommunication monitor system
Password controlled switching system
Path learning feature for an automated telemarketing system
Path replacement in order to remove server used to initiate...
Path verification arrangement for automatically testing...
Patient monitoring system including speech recognition...
Pay telephone applique for subscriber carrier telephone system
Pay telephone with large capacity coin path
Pay-per view catv system