Found in a 1980s publication, this circuit can be modified to use modern components and operate at lower voltages. The power supply does not have to be symmetrical.
We found this circuit in a 1965 magazine. The circuit can be assembled with current equivalent...
This is a typical circuit of a PROM programmer from the 70s. It appeared in the magazine Radio...
If there is an indispensable household appliance in our kitchen these days it is the microwave...