This small audio amplifier uses germanium transistors and a 12 V supply. The circuit is from a Japanese technical documentation from the 1960s.
This high voltage switched generator circuit was found in a 70s American documentation. The...
With this 1-transistor circuit we have a high input impedance and good gain. The circuit is from a...
This wireless intercom has a range of about 300 meters using an integrated circuit that is not...