This circuit doubles the frequency of a rectangular signal applied to its input. The circuit has a 30 kHz input to obtain 60 kHz signals. We found it in a 1964 Electronic Design.
This assembly circuit using a small motor as a generator was found in Radio Electroics magazine from...
This 80s signal follower makes use of an audio amplifier of the era. The circuit can be adapted to...
This circuit is from a documentation from the 70s. Thus, the original transistor no longer exists,...