Alea PCBs are now available for $50USD + shipping.

Each circuit board includes a digital BOM as well as a PDF layout of the front panel for drilling holes in your enclosure (enclosure not included). The PCBs cost $50USD + $7.75 shipping within the US. International shipping rates will be slightly higher and vary depending on destination. These PCBs are lead-free and RoHS compliant.

See below for a Q&A as well as the BOM.

To order - please email:

ouroboros.electronics.us@gmail.com

or place an order via Reverb.com:

https://reverb.com/item/40651461-ouroboros-electronics-alea-pcb-diy-synth-project


Alea DIY Q&A:



Q: Does the Alea DIY project use thru-hole or are there surface mount components as well?

A: The Alea uses only thru-hole components.


Q: There is a notch cut out of the side of my PCB. Is this a design feature?

A: Yes, the notch is to allow space for the banana jack which will be mounted on the top, far left for the square wave lfo (since that one jack sticks out a bit further on the enclosure than the dimensions of the PCB itself, and couldn’t be fit fully on the PCB). Instead of having a large solderable hole for the connection, like all of the other banana jacks, it had the small hole/pad near that corner of the PCB labeled “SQR OUT” which just needs to be connected to the jack via wire.


Q: Do I need to order the exact components listed in the BOM, or can I use other components of the same type and value?

A: Aside from the ICs which must be the exact ones which are specified in the BOM - you can use different components with the same values. Just make sure the voltage rating is high enough, and the parts are roughly as small as or smaller than the parts specified so that they fit well on the PCB and in the enclosure.

Q: I am confused which way some of the components such as capacitors and LEDs should be inserted since not all of the outlines on the PCB indicate the components polarity with a “-“ symbol. How do I know which way these components go?

A: The flat side of the components outline indicates the side on the PCB indicates which side the negative lead should be on. For example, the LEDs negative lead (the shorter leg) should go on the side of the outline which is the flattened side of the circular outline.


Q: Do I need to worry about the ICs being damaged via static shock from my touch?

A: Yes, an anti-static wristband and other anti-static precautions should be own while handling the chips to avoid damaging them.


Q: How do I connect the banana jacks?

A: You can connect them via wire going from the jack to the large circular holes/solder pads which each jack goes through, or you can bend the ends of the jacks down (once all of the jacks as well as PCB are all mounted in an enclosure) and solder the ends of the jacks directly to the circular holes/solder pads. I personally bend the ends of the jacks down and solder directly to the pads, but connecting all of the jacks to the pads via a short bit of wire can be a safer and easier route to go when it comes to disconnecting and reconnecting the jacks from the pcb for troubleshooting on the front side of the PCB (incase that happens to be necessary). The one exception to that is the pad next to "SQR OUT" that will need to be connected via wire to the banana jack on the top left for the square LFO output where the cutout in the board is (since that jack couldn't fit fully on the PCB).


Q: Can I use a 9v battery to power my Alea instead of a 9v power supply?

A: Yes, a 9v battery can power the Alea too!


Q: The drilling template doesn’t indicate what size the holes need to be. How do I know the size to drill the holes?

A: Yes, the drilling template is intended more to give you accurate center points to punch/drill your holes. The sizes of the holes are easiest found by using calipers to determine the width of the part that you’re drilling the hole for.


Q: I have trouble drilling holes accurately. Everything comes out a little off center from the template. What am I doing wrong?

A: Using a “center punch” tool is a game changer as far as drilling accuracy goes. A center punch can be found at Home Depot or Harbor Freight for less than $10. Before drilling, use the center punch to make indentions for each hole in the enclosure using the drilling template (while taped down to the enclosure). Then drill some “pilot holes” using a small drill bit that is roughly the size of the indention that your center punch makes. If you have a drill press - use it. If you don’t, then this can be done with a hand drill, but it’s best to buy or borrow even a cheap drill press to help with this process. After the pilot holes are drilled, next use a “stepped” drill bit to drill each pilot hole to the size that it should be for the knob, jack or LED which will be going through that hole.


Q: How thin does the front panel (top) of the enclosure need to be?

A: It needs to be roughly 3/16th of an inch or less for the nuts of the pots and 3.5mm jacks to be able to be secured.


Q: What should the dimensions of the enclosure be?

A: The dimensions of the enclosures that I make are 10" x 6" x 1.5”. I think that this is an all-around comfortable size for the PCB to fit into, but you could make the enclosure larger if you’d like.


Q: Can I use a metal enclosure for the Alea?

A: Only a non-conductive front panel/enclosure should be used for the Alea as the PCB was designed with a non-conductive enclosure in mind. So to avoid grounding and conductivity issues - only a non-conductive enclosure should be used (such as an enclosure made from wood, plastic, etc).


Q: I don’t have tools or experience in woodworking. What are my other options for making an enclosure?

A: Aside from crafting an enclosure from wood, you just could get a wooden box and drill holes in the top of it. You could also use a plastic project box, or even make an enclosure out of Tupperware or cardboard. You could even avoid an enclosure all together, and simply play the Alea directly using the exposed PCB, and patch it using alligator clips instead of banana plugs!


Q: I finished building my Alea, but something is wrong. How should I troubleshoot it?

A: If it doesn’t appear to be working at all, or something is significantly non-functional, then I recommend checking the polarity of the power supply, then checking the orientation and individual legs and solder points of the ICs and IC sockets. Your ICs may have been damaged by static shock, and if so, then they will need to be removed and new ICs should be inserted using an anti-static wristband. If something minor, or one aspect of the synth seems not to be working, then I suggest checking over each solder joint and orientation of the components (making sure negative leads are inserter correctly, etc). Sometimes, after a long day of soldering, it’s best to just take a break and sleep on it, and it’ll be easier to evaluate everything and continue troubleshooting the next day. Please feel free to send me an email if you are having any problems and I will do my best to help out!




Alea BOM:


1 x Alea PCB


10 x Davies knob

1610AA


8 x 100k pcb mount potentiometer

P0915N-FC15BR100k


2 x 10k pcb mount potentiometer

P0915N-FC15BR10K


13 x black banana jack

108-0903-001


7 x white banana jack

108-0901-001


2 x grey banana jack

108-0913-001


3 x 3.5mm mono jack

16PJ138


1 x 2.1mm 9v DC jack

721A


6 x red LED

LTL2R3KRD-EM


2 x 14pin IC socket (for ICs)

110-13-314-41-001000


1 x 16 pin IC socket (for ICs)

110-13-316-41-001000


1 x CD40106BE


1 x CD4015BE


1 x CD4069UBE


(All ICs (CD40106BE, CD4015BE, CD4069UBE) must be the exact part specified. I recommend ordering a couple of backups for each IC, just incase. You will be able to replace them in the socket if something goes wrong.)


2 x 100uf capacitor

REA101M1CBK-0611P


3 x 10uf capacitor

RGA100M1HBK-0511G


3 x 1uf capacitor

C440C105M5U5TA7200


2 x 0.047uf capacitor

SR215C473KAA


6 x 0.1uf capacitor

K104K15X7RF53H5


4 x Diode

1N4148


3 x 100k resistor

MFR-25FBF52-100K


2 x 40k resistor

CMF5540K000BHEB


10 x 10k resistor

MFR3-10KFC


1 x foot of red lead wire

1 x foot of black lead wire

2 x foot of hookup wire


Parts to make your own vactrols:

5 x green LED (for vactrols)

C5SMF-GJE-CV0Y0792


5 x LDR (for vactrols)

Adafruit 161


5 x heat shrink tubing (for vactrols)

ES2000-NO.1-C1-0-27MM (this is a good size, but the pieces will need to be cut slightly shorter to fit on the PCB)


If you have never made vactrols before - it is a simple and easy process which can be learned via this Youtube video:

https://youtu.be/8BOnvSQpoGY


For enclosure:


The enclosure of the Alea needs to be roughly 10” x 6” x 1.5” or larger.

I designed the PCB with a non-conductive enclosure in mind, and the PCB is not intended for use with a conductive enclosure.


If you would like to make an Alea out of wood, then you can use this steel plate on the bottom:

1 x steel hammond piece

1431-16 (grey)

or 1431-16BK3 (for a satin black option)


You will also need screws for the steel piece. I use #4 - 3/8” screws.


If you would like rubber feet for your project:


4 x Adafruit small rubber feet

550

PDF Template for Drilling:

https://drive.google.com/file/d/1TnuO0FEnDdWDiS08lz5ZwZCZSWSWLLsg/view?usp=sharing

ALEA PCB DRILLING TEMPLATE V2.pdf