This circuit has a sensitivity of 2uW. We found it in documentation from the 1980s. The integrated circuit is from that time. Equivalents can be tried.
This interesting circuit for SMD assembly appeared in the November 1987 issue of Radio Electronics...
This circuit was found in the June 1986 issue of Radio Electronics magazine. It is based on two...
Found in a 1980s documentation, this circuit works with a 12V relay. The horn is the boat's own. |...