This generator is more complete than the previous one, being able to generate pulses as indicated in the table next to the diagram. In the original, a 556 was used which is a double 555.
The integrated circuit used in this application is not very common. The circuit is intended for...
The focused circuit was found in the National Semiconductor's Linear Applications Handbook of...
The TDA2040 is not a common IC these days, but if you find one you can build this high quality...