The circuit presented is a documentation for radio amateurs from 1978. Implemented with common CMOS and linear components, it indicates CMOS logic levels.
We found this circuit in an old publication. The ICM7556 is a dual CMOS 555. The other components are...
The operational used is uncommon today, but equivalents can be used. Unlike the previous one, this...
This musical doorbell was found in a Popular Electronics from the 90s. The U4 melody generator...