This simple 555 component tester was found in the November 1992 issue of Radio Electronics magazine. The circuit is powered by 6 to 12 V batteries.
This amplifier was found in a Japanese publication in 1972. Transistors are uncommon today, and...
The current of this source is 200 mA at the most, and the output depends on the zener that may...
Found in Mallory documentation from 1968 this circuit uses an integrated circuit from that time. The...