Witches Brew CV Joystick Controller

I really like the Front panel that I made and will probably go with a similar layout/Graphics very easy to visually see the control for each knob. The control pots are directly connected via the 5-pin DINs connectors. Still need to do a proper Re-Design the Kosmo format is very popular now.     

I am revisiting this project and Trying some new prototypes. I am thinking of redoing this project into Kosmo Format. Now that it is pretty popular community behind it. Gonna be a fun ride.       

After building some of the PCBs for the witches brew v1.3.1. Found out that it seemed like the LEDs were not working at all. After going through quite a bit of trouble shooting of checking simple stuff like polarity and even breadboarding a separate circuit based on the original schematic I drew up. It looks like I messed up on the Power Decoupling Capacitors. Planning on using these ones for a Separate Project anyway and the rest BODGE wires away! 

There in v1.3.1 there is a option to add a always inverted switch. So this simple mod you can add it if you want. 

The first Inverted output version, I tired the idea with a separate Inverted CV Jack. 

But as someone pointed out that the way the circuit works if you tweak of offset knob it wont just effect the the first CV jack with the offset knob, but also effect the Inverted output switching polarity too which kind of defeats the  propose of it being a always Inverted Output.   

 I am looking into designing one that has a Always Inverted CV output. But it would require more work to function properly and a full redesign with 2xTL074.  Tomas Henry MFOS Quad DC Modulation Mixer has something very Similar  and is a interesting read if you want to learn about Op amp Mixers.   

I have to say looking back on the first PCB layouts. My skills have a quite a bit of improvement Between versions of PCB  layout. In Planning out sections of the board and optimizing placement of components. Quite a bit of things you should plan out before even thinking about doing the traces. 

My first designs were so Simple the autoroute worked perfectly fine. But soon as I added complexity too the placement it would eventually give up on completely routing. I brushed up on manual routing and common good practices. I found the use of a auto router is a good base for starting manual routing. Then doing manually is just like putting a puzzle together. 
I also learned about using Copper infill and Ground planes for the Double sided PCB and why it cleans up quite a bit of the grounds and +12v Rail. Before using these Manual routing started to become a nightmare becoming quite the rats nest of wires.   

I cleaned up the rats nest of traces. It seems it went quicker. Now have more experience with Easy EDA.

•Added a +12v copper infill on the Top Layer for the Power rail too clean it up a bit.

•Removed the Passive Attenuator, Because of testing I found it pretty redundant with already having a range knob. No need to complicate things.

After further use of the Witches Brew.  I decided that the passive attenuator section is pretty redundant with the range knob. No point in having it making things more complicated and take more time too build. I am also adding the Option to have a Inverted X/Y output. Too add more flexibility too the module.  Things have been Slow, But it shouldn't take long too redo the PCB. This is a great article about Offset Scalers. I found this when Modular in a week introduced me too that page and was a interesting feature too add. 

For anyone interested, This is a video demo of LMNC AD/AR module and a patch with my system controlled by the witches Brew module. I would like to thank LMNC for giving the community projects some spotlight. Kosmo System Project Feat. Witches Brew Control voltage Joystick

After doing the PCB Layout and redoing some of the Artwork. I present you a very close Representation of what a final PCB will look like. I would like too thank Kristian Blåsol for his series Modular in a week for teaching me and pointing me in the right direction. 

Also LOOKMUMNOCOMPUTER for teaching how to motivate myself and not get down when things don't work as planned "Don't be afraid to try it." Been Though so many failed circuits and Burned IC's. But was able to make something out of it. 

So after some testing and Reading other methods of driving LEDs. I decided on Converting the output voltage to Current Source. That it would be the best way to Linearly display the output voltage. While my original idea did work to drive the LEDs they would Cut to zero Brightness(Lumis) still at 500mv output. That is because controlling it by voltage cannot be completely linear Due to the LED forward voltage. Now that I am controlling them by current we are actually able to accurately Display the voltage on a Blue and Red LED. Now that I solved that problem. I'll Re Design the PCB too incorporate these changes. It was pretty fun finding a fix for this.