This commercial transistor tester circuit (EICO 666) is from a Japanese publication from the 1960s. The switch selects the types of test with the switching of the terminals and the gain ranges.
This circuit was found in a Signetics documentation from the 1980s. The integrated is a PLL and...
This two-channel wired intercom was found in the April 1990 issue of Radio Electronics magazine....
The output voltage of the circuit shown in the figure is approximately 7.0 V for a 15 V supply...