This 6-transistor Japanese radio for the medium wave range was manufactured in the 1960s in Japan. The circuit is superheterodyne with a 6 V power supply.
We find this efficient emergency lighting system in a 1987 publication. The circuit keeps a...
We found this circuit in a 1976 documentation. The FET can be the BF245 and the bipolar transistor a...
The shunt type regulators are connected in parallel with the load, deflecting the current to...