This circuit can flash for up to 30 months using alkaline batteries as shown in the table next to the diagram. The circuit is from a Radio Electronics from January 1992.
In the figure below we have the way to connect solar cells in parallel to charge a battery in an...
We found this parallel regulator in a 1973 publication. Transistors admit equivalents and the...
This circuit can be found elsewhere on this site as part of alarms or sirens. The circuit given is...