We found this configuration in a 70s American documentation. The circuit makes use of operational amplifiers of the time. Modern equivalents can be tested.
Using a CA3130, we found this circuit in an English publication from 1977. The circuit must use a...
We found this circuit in a 1980 documentation. The flasher uses 3 transistors in the configuration of an...
This circuit was found in General Electric's 1965 documentation. It appears elsewhere on the site....