This circuit was originally recommended to give the call signal on intercoms. However, it can be used with other applications. The circuit is from 1978 documentation. The transistor may be the BC548.
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...