Wednesday, March 6, 2013

8038 Triple LFO module

I would avoid building this module.  I ran into so many problems trying to find 8038 chips that I liked.  I decided instead to build a different BETTER LFO module.  that post is HERE.  If you have some 8038 chips laying around with the correct numbers on the, then, this could work for you.....

I recently built a pretty simple but very useful LFO circuit with the ICL8038 chip.  I decided to go ahead and build a triple LFO module in a double wide panel.  I took the time to make a nice PCB for the circuit with fat traces and solder pads.  When I finished and assembled my module, I was surprised to find that two of the three circuits didn't seem to be working correctly.  They had a limited range.  after checking all my traces, I realized that the two which were not working correctly were newer chips from a different batch/seller.  The one that was working was from the first module I built.  ultimately, I decided that the different chips did not work with my circuit.

this chip works with the circuit

and this chip doesn't


I tried ordering more chips with the correct numbers based on the picture of the chips on ebay and they sent different chips that didn't work.  I'm really annoyed with the 8038 chip situation. So, I'm going to revisit this LFO project with a different circuit,  one that doesn't utilize the 8038. 

So,  go figure.  Anyway,  here's the PCB.  I'm not going to spend a lot of time explaining this circuit because I did so in an earlier blog, HERE

So,  I've included the single LFO parts reference because it explains the how to wire the two potentiometers.

The triple LFO is on the right hand side.  In the center is my sequencer which will be included in the following blog. 


  1. I made it. It is the excellent module.
    Regards from Ukraine!