We found this circuit in the 1982 SGS linear integrated circuit manual. The L149 is not common today and the circuit can be implemented with equivalents.
This circuit was found in an English magazine from 1973. The magazine no longer exists, but the...
This radio version of 1 transistor, extensively explored on this site and in this section, is from...
This dual control was based on Texas Instruments documentation for the CD4050. The circuit has two...