This interesting digital counter with relays with complementary outputs was found in the Radio Electronics magazine of October 1961. The supply voltage is in accordance with the relays used.
In the figure we have three voltage doubler configurations that can be used in high and low...
In this application, from English documentation, we have the way to activate an AC load up to 10 W...
This 1-transistor reflex receiver was found in a 1963 publication. The coil is for the mid wave...