This circuit was found in old documentation, however the components used are common today. The selection of times is done by switch and the 556 consists of a double 555.
Using the LM3909 this circuit was found in the January 1992 issue of Radio Electronics magazine....
This circuit allows the coding of several relays from coded keys that must be activated, according to...
To power small projects, we found this circuit in the Radio Electronics magazine of May 1977. The...