This circuit is from a Radio Electronics magazine from February 1992. The circuit has the effect speed dependent on C1 and adjusted by R3.
This circuit was fond in an old publication of the years 1950. The transistors are germanium types and...
This circuit uses two TTL trigger inverters to generate signals that can be adjusted at R1. The...
This circuit is from a 1977 Radio Shack documentation. It produces a modulated sound of good...