This commercial signal follower was found in a 1967 Japanese magazine. It uses germanium transistors and provides a speaker output without the need for a transformer.
This simple photometer uses a 1 mA milliammeter and a common phototransistor. The circuit has its...
The component values depend on the current, which in this case has a maximum value of 5 A. The...
I found this circuit in an article in a 2003 publication. The circuit is an example of how to...