This circuit was found in a Popular Electronics from the 90's. It consists of the solid-state variation of the well-known grid-dip meter. MOSFET is a component not very easy to obtain these days.
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...