This two-digit timer was found in the 1983 Special Projects issue of Radio Electronics magazine. The circuit uses components that can still be found today.
This circuit was found in 1966 General Electric documentation. The circuit uses components from the era...
We found this circuit in a magazine 73 for radio amateurs from the 80's. The circuit makes use of an...
This circuit uses one of the first comercial transistor and is from a 1958’s magazine. Tone...