This circuit is from 1980s documentation. The maximum operating frequency is 3.5 MHz. The current of the LED can be from 0 to 100 mA. The integrated circuits used are from that time.
We found this circuit in a French technical documentation from 1982. The circuit can be...
This simple alarm for doors and windows was found in a Japanese publication from the 1960s. The...
We found this circuit in a documentation from the year 2000. This circuit appears on the site...