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 unity gain circuit was found in the February 1995 Electronics Now magazine. The frequency is 10 kHz,...
Found in a 1967 Electronic Design, this transistorized circuit compresses and then expands a pulse....
This TTL pulse stretcher or stretcher was found in a 90's EDN. The time constant R x C1 determines...