This is it. It`s a STEREO LED LEVEL METER. It`s the cheapest and best bar graph display available and best of all, it uses readily available components.
You only need a handful of LEDs, 22 transistors, some resistors, diodes and a set of electros - it doesn`t require any chips.
You may be wondering why we didn`t choose the LM 3914 or LM 3915 bar-graph LED driver chips. The reason is simple. We learnt our lesson from our Mini Frequency Counter Book. In it we used a relatively novel chip, the CD 4026. And after releasing 10,0