Found in Radio Electronics from May 1959, this transistor tester is quite sophisticated. The circuit uses a 1 mA analog indicator.
Found in an Electronic Design from the 90s, this circuit uses high voltage operationals of the...
This circuit was found in the July 1990 Radio Electronics magazine. It is based on the 3-digit...
The circuit shown in the figure uses two of the four operational amplifiers found on the LM324...