The integrated circuit of this amplifier is not very common today. The output transistors can be TIP31 and TIP32 in heat radiators. The circuit is from the 1977 National Semiconductor Audio Handbook.
The contact of the sensor with water or humidity causes the relay to close its contacts. The...
This siren was found in a 1980s documentation. The circuit makes use of very old operational that were...
This circuit was obtained from Motorola documentation from 1969. The setting applies to other...