This integrating circuit multiplies the time that can be obtained with a 555 timer. We find it in an Electronic Design from the 90s. The circuit uses components that are still common today.
We find this ultra-simple transmitter circuit that is nothing more than a very short range RF...
The circuit shown is from National Semiconductor's Linear Applications Handbook published in 1994....
This configuration that appears several times with variations on this site is from old American...