How to Bananafy a Korg SQ-1

After building my Buchla system and now my 73-75 Serge panels, I've been looking for a means to sequence the banana-laden synthesizers. After eyeing my SQ-1 sitting on the shelf, I decided to test out the voltages and see what is happening. To my pleasant surprise, the gate outputs on the SQ-1 are hot enough to trigger all my different Buchla modules. Although the SQ-1 only puts out v/oct and Hz/Volt and not 1.2v/oct, I still find it to be a useful module. Eventually I'll add a conversion board inside but, for now, it's great.
An added bonus of the SQ-1 is that you have 2 channels of USB-MIDI to cv/gate conversion. The only thing that's a little funky about the SQ-1 is that it isn't 100% class compliant. The only time I've noticed an issue with this is when I try to connect it to the usb-host jack on the iConnectMIDI4+.

The conversion itself is fairly simple. I've done 2 so far and each one took under an hour. The cost is the cost of an SQ-1 and 5 banana jacks. Right now it is the holiday season and you can get a new  SQ-1 below full price.


The first step is to remove the 4 philips screws on the side of the unit along with the 4 hex screws on the top. Remove the selector knob.



The unit should come apart but be connected via the 2 wires for the battery connection. Be gentle not to break these wires. Unsolder them to make the rest of the process easier.

Now that you have separated the top and bottom housings, remove the 6 screws that hold the main circuit board in place.



Add in your banana jacks to the top housing. Make sure to bend down the metal tabs to make sure they don't make contact with the circuit board below them. I used Cinch banana jacks and they fit in with no problem.





Solder wires to the banana jacks. Don't make the wires too long or else it'll be difficult to fit them in. Don't make them too short or else it'll be difficult to solder them to the circuit board.




On the circuit board, remove the jacks that you don't want. I chose to turn the LittleBits jack into the ground jack since I don't plan on ever using LittBits.
The plastic housings for the jacks are easy to pop off by hand. This exposes the metal prongs. With pliers, you can heat up the pads and remove the corresponding metal prongs. No need to use solder wick to remove all the solder from the holes since we'll just be soldering back on to them.



On the back of the board, make sure to bridge the 2 sets of pins as shown in the following picture. These pins correspond to the switch in the gate out jacks. The SQ-1 tries to do something smart with normalization with the gate outs, but, this is no use to us so we need to trick it into thinking a jack is plugged in. 


Solder the wires to the corresponding pads as shown in the picture below. Note the ground (black) banana jack goes to the ground pad whereas the other 4 go to the signal pads. 


Carefully put the circuit board back, screw it in, and test everything out. Make sure you have analog voltages coming out of the CV outs and gates going out of the gate outs.
Put all the screws back where they were and enjoy your new bananafied sequencer!



Github Projects and DIY Synth Modules

It's been a while and I have been keeping busy.

I'be been slowly curating my github with open source firmware and hardware projects. 

All of the open source circuit boards have been designed in Altium and their files are available with the projects. You will also find a zipped up folder in each project that can be sent directly to a PCB board house for manufacturing. If you ever have a problem with a board house accepting the files, please reach out and I'll help you out.
I strongly recommend PCBWay for board fab. I've have 12 boards fabbed by them and I've never had a problem. They always ask the right questions if they are unsure about something but they don't barrage you with e-mail likes Sierra Circuits (never ever use them). PCBWay make everything easy and from quote, to file submission, to payment, to tracking the progress. I usually get the boards in my hands 2 weeks after I submit the files and the prices are some of the cheapest I've encountered. Often times, PCBWay is even cheaper than places like OSHPark.

I have also been slowly building a Buchla system from scratch. When it is complete, I'll write a post about the process and provide some video examples.

Sound Nicer

My newest module is the Sound Nicer.
It is based of the CoolAudio V2153. 
It is a sonic maximizer expander type of deal.

Fab files and Altium project files can be found here: https://github.com/auxren/SoundNicer

TripsQuad: Quad Waveshaper

My first eurorack module design is a quad waveshaper called the TripsQuad. 

It is open source and you can build it yourself. All the files for fab and assembly are here:
https://github.com/auxren/tripsquad

Here is a demo of the first prototype:

Simple DINSync Breakout Box

I recently got really lucky and picked up a TR-606 for stupid cheap.
I made this simple little breakout both to interface with my eurorack system:


Just 4 jacks. Cut the end off a MIDI cable and broke out the cables in the box.  


The DINSync jack on the TR-606 puts out Clock, Reset, Start/Stop, and Fill. The box can work as an input or output source for the syncing, so my 606 can act as a master or a slave. 



Updating Industrial Music Electronics STILLSON HAMMER MKII

The update is pretty simple. I have tried it with a MAC and not with Windows yet, but I believe MPLAB IPE has the same process for both. 

You'll need a PicKit. I have a PicKit3 and haven't tried it with a PicKit2.

Download MPLab HERE

When downloading, make sure to select MPLab IPE and unselect IDE unless you want the full development suite.

Once you finish the download, open up MPLAB IPE.

Under device, type in 'dsPIC33FJ128GP310A'. That is the MCU used by the Stillson Hammer.
With your PicKit plugged in, you should be able to see it show up under tool. Connect to it. 

On the source line, select the Stillson's firmware.

Plug your PicKit into the back of the Stillson as shown:

Click program and it should run through it's little process of programming.

When complete, restart your system and you should see 1.500 firmware on your Stillson:



Pixmob Smart Lightup Bracelet Teardown

I recently had the chance to attend game 1 of the NBA finals in Oakland's Oracle Arena.
It was an amazing experience that landed me an all access pass to the Arena for games 1 and 2. The purpose of my visit was to test out my day job's product in the environment. Being that the product involves RF communication, it was a complete flustercluck of frequency chaos. I arrived early and got a chance to meet with the NBAs contractor for 'RF Coordination'. The head honcho explained to us how they try to regulate all the frequencies in the arena so people can freely communicate as they need. This includes event staff, ESPN folk, food people, ushers, and anyone else with a walkie. He mentioned that the 2.4 GHz and 5 GHz ranges were free range since they are near impossible to regulate, which makes sense. He also mentioned that reps from companies like ATT and T-Mobile were there checking their licensed spectrum to make sure no one encroached on their airwaves. All really cool stuff, but I digress since the purpose of this is to tear apart the bracelets given out.

Upon walking into the arena, I noticed that every seat had the 'Strength In Numbers' shirts along with bracelets masking taped to each seat. There was obviously some magic to these bracelets; they couldn't just be silicon bands with plastic tops. 

After getting my initial work done, I settled down in the media section and waited for the game to start. John Legend came out to sing the national anthem, the lights went down in the arena, and all the bracelets started lighting up. Not only were they lighting up, but the the colors were coordinated by section where some were red and some were blue. It was an amazing sight. 

Throughout the game, the bracelets would again light up. Also, clapping your hands seemed to set off the lights on the bracelet. When I had a few minutes break between running around and working, I used LightBlue to sniff the BLE in the area since I considered the light-up coordination was done via a BLE mesh network. Could it be that Pixmob was able to manufacture these bracelets with BLE at such a low price that they can be giveaways? Upon scanning, I found hundreds and hundreds of unnamed BLE devices around me. Red herring?? Also, is it possible Pixmob also threw in cheap accelerometers for the hand clapping detection? 

 Fast forward to the next day after work and I am home with this bracelet that still lights up when I clap. It's ready to be opened up. 


Two CR2032 batteries to power the device.


First thing I notice when cracking it open is the RGB in the center. Pretty standard lil' dude. Then I notice, no RF. So there is no BLE? Instead there is an IR reader. Could all the color coordination by section be done by IR? I guess so!

On the sides, we see 2 more RGB LEDs completing the complement of 3 RGB LEDs on the device.

I then noticed SW1 (the white cylinder). It's too small for pictures, but there are 2 leads coming out of it. One is a thick lead connecting to metal on the outside perimeter of the cylinder and one is a tiny thin wire in the center. Ahh!! The ol' spring contact trick! Inside SW1, the thin wire goes to a spring floating in the center. When the user shakes the bracelet, the spring in the middle makes contact with the metal on the perimeter which allows the microcontroller to know 'hey, time to light up these RGBs!' 

Speaking of microcontroller, what powers this guy? Seems that it is a MC81F4204 by a company called Abov. The MCU is a CMOS based 8-bit MCU with 4k of flash and 192 bytes of RAM. It has a 12-bit ADC and other basic features. The part doesn't seem to pop up on Octopart. Wonder how cheap they are in quantity. You can also see solder pads around the MCU. The geek in me hopes they are pads for a scalloped RF module incase you want to get real fancy with the board, but it's probably just for a larger IC along with programming headers (J1).

Overall, a cool little device with some nicely done DFM to bring down cost. 
Hopefully I can grab more when I'm at game 2 so I can hack em together and see what I can manage. 

Go Warriors!