100 LED Oscilloscope

...

This looks like a great project.

uses only 4 ICs

555 timer

4017 decade counter

LM3914 ... its a dot/bar display driver

LM386 ... amp

 

 

It's a solid state scope that uses LEDs to display.

 

The LM3914 is a monolithic integrated circuit that

senses analog voltage levels and drives 10 LEDs,

 

Wouldn't have great resolution, but excellent for visualising waveforms.

Something like this would be excellent to supply CVs to a modular synth.

You can find a similar circuit on page 108 of The Forrest Mims Engineer's
Notebook. 

 

The circuit for this scope was also published in August of 1979 in Popular Electronics  

(page 72)