|
US3691593A
|
|
Data dialing transmitter
|
|
GB1326294A
|
|
Data reporting system
|
|
CA932486A
|
|
Data reporting system
|
|
CA939816A
|
|
Decimal to binary converter
|
|
US3611409A
|
|
Time code recording device
|
|
US3588482A
|
|
Decimal to binary converter
|
|
US3390234A
|
|
Combination telephone fire alarm and meter reading system
|
|
US3369079A
|
|
Automatic telephone alarm reporting system responsive to changes in voltage across subscriber's telephone lines
|
|
CA807313A
|
|
Telephone reporting system
|
|
CA832562A
|
|
Telephone fire alarm system
|
