Answer supervision circuit for paystation telephone with non-mut

Coin blocker

Coin charging system for mobile telephony

Coin relay drive and switching circuit for paystation telephone

Data communication circuit and method using telephone system

Dynamic microphone handset and amplifier unit

Face plate with ad frames for coin operated telephone boxes

Handicap telephone with associated booth

International speaker telephone

Method and apparatus for keyboard adaptation to a low power cont

Multi-function general purpose transceiver

Multi-function general purpose transceiver

Multi-function general purpose transceiver

Pay station telephone call routing apparatus

Plug-in telephone facility

Public communications services vending method and apparatus

Public telephone volume control

Public telephone with and method for cash payment function

Safety seat stand apparatus for coin-operated telephone sets

Telephone system and method operated from central office loop cu