|
DE872528C
|
|
Device for monitoring voice-controlled apparatus
|
|
US2608608A
|
|
Electrical relay system
|
|
GB655937A
|
|
Arrangement for speech control of installations such as telephonographs
|
|
US2553410A
|
|
Device for eliminating silent periods between intermittent recordings
|
|
GB628625A
|
|
Improvements in or relating to impulse recording apparatus
|
|
GB599828A
|
|
Sound carriers
|
|
GB624687A
|
|
Arrangement for switching on and initiating processes by means of telephone calls
|
|
US2489638A
|
|
Arrangement for switching on and initiating processes by means of telephone calls
|
|
DE868456C
|
|
Electrical remote control of a switching device belonging to a subscriber station in a telephone network
|
|
GB588440A
|
|
Means for the remote control of telephonographs
|
|
CA495057A
|
|
Electric impulse switching and process-initiating means
|
|
CA487796A
|
|
Arrangement for the tele-release of electrical processes
|
