This is a very useful autotransformer circuit on the bench. We found it in the September 1970 Radio Elecronics magazine. The transformer must be according to what you want to feed at the output.
This circuit was obtained from the November 1989 issue of Radio Electronics magazine. The circuit is...
This simple digital frequency meter using CMOS circuits reaches 5 MHz frequency. Input signals are...
We found this circuit in the 1960 Mullard transistor manual. The transistor is made of germanium....