This 1-transistor circuit for currents up to 50 mA was found in the August 1974 Radio Electronics magazine. The transformer is 50 to 200 mA.
This medium wave commercial receiver from the 1960s was found in a Japanese publication at the...
We found this circuit in a 1967 Electronic Design. The circuit used a MOSFET of the time, which is...
This step of two transistors has a high input impedance due to the use of FET. We can use BF245 for...