|
US2182119A
|
|
Remote control system
|
|
GB497727A
|
|
Alternating current signalling or control system, applicable particularly to telephone systems
|
|
DE678314C
|
|
Thermopneumatic fire alarm
|
|
GB470902A
|
|
Improvements in or relating to thermally operated fire-alarm apparatus
|
|
GB469869A
|
|
Improvements in or relating to signalling or remote control systems
|
|
US2209883A
|
|
Remote control system
|
|
DE678376C
|
|
Arrangement for transmission of signal or control processes with the help of alternating currents
|
|
GB473373A
|
|
Improvements in or relating to thermally operated fire-alarm apparatus
|
|
DE681562C
|
|
Testing device for pneumatic fire alarms
|
|
GB284296A
|
|
Electric remote control systems
|
