Охранные устройства и сигнализации

Coded locks are rather widely applied to restriction of access of extraneous persons to protected objects. Convenience of using such locks consists in possibility both individual, and collective access (pass to service premises, access to left-luggage offices, etc.). Fig. 1....

When I faced need of manufacturing of such device, that, having studied the whole pile of literature, came to a conclusion that any of earlier published circuits completely is not suitable for these purposes. Therefore also it was necessary to be engaged in manufacturing of own system which would possess simplicity...

I offer the simple acoustic automatic machine for turning on of various actuation mechanisms. The essence of work of the circuit (fig. 1) consists in the following. At a certain level of acoustic noise near the high-sensitivity BM1 sensor microphone, threshold which level of inclusion is established...

Security alarm system. switches for household devices, control sensors on the production conveyor — here only small part of scope of this capacitor relay. It can be used, for example, in the elementary household automatic equipment: sat down in a chair — the floor lamp joined, music played...

From a fire the damage can be even more, than from thieves, and in time the submitted alarm signal will allow though something to rescue. Fig. 3.21. An electric circuit of the sensor of a smoke On industrial facilities thermal sensors (they are cheapest) are generally used for the alarm system about a fire. Their feature...