…The baby was cranky for a long time and finally fell asleep. A few minutes later the doorbell rings. And, of course, the baby wakes up, and now to calm his unlikely…
I propose a simple addition to the doorbell. Just say that it’s good for calls that are switched through the circuit of 220 V. Here we need a cartridge with a bulb and the switch. Everything is connected as shown in the figure. In normal mode when you press the button is actuated and a bell, and a lamp in the “quiet” — only lamp.
I. GALKIN, engineer
Recommend to read
“AERODZHIP”: FROM DESIGN TO MACHINE
Student design Bureau of the Riga red-banner Institute of civil aviation engineers named Lenin Komsomol familiar to the readers of our magazine. Development of Riga have been...
CONVENIENT SOLDERING IRON
The soldering iron is any homebrew. But those who have to deal with modern electro - and radio equipment, this tool is something special. And the requirements for it are quite hard: with...
