(Part 2) Best products from r/synthdiy

PCB/Schematic Capture

>To jump right into schematic / PCB layout, I'd use EasyEDA because you can finish that layout and order boards directly from their sister company JLCPCB. EasyEDA is super easy to use, and usually has all the schematic libraries you'll need.
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>Moving on from EasyEDA, go to KiKad definitely. I believe EasyEDA is more user friendly for the basics, so definitely start there to get a good grasp.

Learning

>For learning electronics, start by diving into some informational YouTube channels. Ease yourself into all the jargon and terms. It will be very overwhelming at first, don't be too hard on yourself. Try to learn what most components generally do (i.e. transistors are just switches, capacitors act like batteries, etc.) GreatScott has some good beginner videos iirc.
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>Buy Make: Electronics and go through every exercise. This will really help you understand how certain things work, and improve your troubleshooting.

Regarding your comment about understanding circuits, it can be very difficult - especially in your position as your are looking at these rather intricate synth circuits. Music From Outer Space generally has great write ups on how his circuits operate, but man sometimes those explanations go over my head and I'm an EE. Read slowly, and google any concepts or words you don't know. Break down the circuit in chunks and analyze chunk by chunk - what does each chunk do? Reading and understanding schematics is a skill that will develop over time most definitely.

I haven't built Tides2 yet (it arrives in the mail tomorrow) but I've done some of the other 0402 Mutable stuff recently. Personally, I can't imagine doing even 0603 with an iron... it's too fiddly and the boards have too many parts.

Get a hot air station from Aliexpress and some stencils from OSH. The hot air station is awesome, I can't believe it was less than $20 -- despite being labeled 858D, it does NOT have the wiring / grounding / fuse issues that I've seen other people complain about this model who bought it a year or two ago. Everything is electrically correct and it works great. I use it with no nozzle attached and at the lowest air speed (which seems fast to me, sometimes I actually hold a finger over part of the air intake to slow it down a little bit).

I also recommend some inexpensive magnifying glasses from Amazon (links below). My preferred solder paste is Chip Quik SMD291AX10T5. Get some SMD practice boards from Ebay so you get the hang of the hot air station before you try the real PCB. They're like $1 each and include several different parts to practice with.

I've done 8+ Mutable boards in the past month with this setup (some are 0402, some have CPUs with fine pitch pins) and haven't had any major issues. Everything works. Just make sure you follow general proper procedures such as knowing how to read the Eagle files, how to test for shorts, how to follow the signal around the PCB, how to program the CPU with the JTAG/SWD interface (and how to set up the Mutable Dev Environment)... and it should be easy.


https://www.aliexpress.com/item/32818260663.html

http://oshstencils.com

https://www.amazon.com/gp/product/B078JPRH2Y/

This was my first time attempting to solder on a PCB. If you are looking to get started with DIY builds I would recommend this kit. The instructions are in color with easy to follow steps. Coming from zero experience this was a huge help for me.

Tools Used:

Soldering gun

60/40 no clean flux core solder

Scotch tape

I didnt take pictures of every step. The board was pretty easy to build. I used tape to hold components in place. This was my first attempt at soldering anything on circuit boards but lots of guides on YouTube show you how to do it.

Specs on the psu and board.

100-240vAC Mains AC Input

Expandable - You can daisy chain up to 5

10,000mA Symmetrical Current Capacity

5,000mA Max Load +5v & +12v combined

5,000mA Max Load -12v rail

1,000mA Max Load Per Bus Board +5v rail

15 Power Outlets Per Bus Board

User Replaceable Power Bricks

The kit comes with power bricks and a 4HP module if you want to feed it nicely out through your rack. I screwed this module up so I am not using it. Lesson learned though - Place LED's between both circuit boards before soldering to ensure proper fit. You can buy everything a-la-carte which is what I did for the second busboard.

22 AWG stranded wire is pretty standard for wiring anything.

i usually buy these, as they're a good price, 2 day shipping w/ prime, and its a nice multi color kit, which helps when wiring...in case you have to trace the wire back to the board when debugging. plus everyone likes colors:

http://www.amazon.com/Electronix-Express-Hook-Wire-Stranded/dp/B00B4ZQ3L0/ref=sr_1_1?ie=UTF8&qid=1418566941&sr=8-1&keywords=wire+kit

http://www.amazon.com/Electronix-Express-Hook-Wire-Solid/dp/B00B4ZRPEY/ref=sr_1_2?ie=UTF8&qid=1418566941&sr=8-2&keywords=wire+kit

use shielded wire (with the 'shield grounded') for any audio signal inputs/outputs if you get noise. not 100% necessary, but might be worth it in the end for the sound quality and reducing any noise.

i also recommend you get a real wire stripper. this one is the bees knees:

http://www.amazon.com/Tools-VISE-GRIP-Self-Adjusting-Stripper-2078300/dp/B000OQ21CA/ref=sr_1_2?s=power-hand-tools&ie=UTF8&qid=1418567132&sr=1-2&keywords=wire+stripper

You might really enjoy reading (Electronic and Experimental Music by Thomas Holms)[https://www.amazon.com/Electronic-Experimental-Music-Technology-Culture/dp/0415896363]. I found it at my college library when I was looking for anything to keep the high of my Moog factory tour going. I'm really glad I stumbled upon it, and am still debating adding it to my bookshelf at home.

It thoroughly documents the history of electronic music, which Holms roughly describes as the history of music that does not need a human to be performed. It starts off in the late 1800's I believe and continues until contemporary synthesis. There's a lot of discussion about early researchers, organized by country of origin, and recording outputs of function generators onto tape reels and splicing tape to compose. The second half is then about synthesizers and techniques that are more akin to what is used today, in the modular to keyboard style machines.

Really a phenomenal history book, and a pleasant read, with interesting diagrams and photos of the old equipment, and diagrams of concepts being discussed.

I use this Weller Soldering Station. Weller's are pretty tried and true but are not top of the line. But for synth DIY, I find this station more than capable and a good deal too.

Op-amps: the TL072 is one of the most widely used, it's cheap, and it works fine in most situations. It has two small drawbacks for some applications: it needs a dual supply, at least -/+5V, and it's not a "rail to rail" op-amp, so it needs some supply headroom above and below the signals you plan to put through it. Some other op-amps can do rail-to-rail with a single +3V supply, for instance, which makes them potentially easier to use with a modern low voltage MCU (some Arduinos/Teensys/etc.). But if you've got the power supply set up properly, the TL072 will be great.

Audio Out: You'll need to match voltage levels and have some sort of output driver.

If you're going to a line out (like to a mixer or stereo receiver) you want to aim for a max of about +/- 1V and you can use any old op-amp to buffer and level-shift the signal on the way out. Here's a handy worksheet for designing the level shifter.

I haven't done a headphone driver; I know different headphones have vastly different specs, and my research here has been really confusing! I do believe typical op-amps won't provide enough output current to reliably drive headphones, though -- traditionally something like an LM386 is used.

Assorted parts: If you're experimenting, just buy a big kit package of resistors, one of ceramic caps, one of electrolytic caps -- like 200-to-1000 piece kits, 10 to 20 each of 20-40 different values.

Transistors, get a handful of 2n3904 and 2n3906, those are general purpose BJTs in NPN and PNP configuration. Also some 2n5457 N-channel JFETs. 1N4148 diodes are fine for all the low-voltage signal stuff.

Check out Sparkfun or Adafruit for breadboardable switches, buttons, and other goodies. Adafruit tends to be a tiny bit more user friendly and Sparkfun a little more towards the I'm-gonna-build-a-flying-killer-robot-in-my-garage crowd. Both of them offer breadboard and jumper wire kits. I love these precut-and-color-coded-for-length wires for keeping breadboards super-tidy; others prefer the freeform jumper wires.

You're gonna want a soldering iron soon. A low-end temperature-controlled soldering station is IMO worth the money over a dumb iron; I've got an X-Tronic 3020 but other people swear by Hakko. Pick up a set of finer chisel tips than the iron comes with. A big silicone soldering mat, QuadHands, desoldering wick will come in handy too if you've got the budget for them.

Sounds good. I find it amusing that you played it upside down.

Is that scope one of these?

https://www.amazon.com/gp/product/B0195ZIURK/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I am almost done building one with the intention of using it in my eurorack setup. What does the nob do on it?

Looks like the XR2206 based function generator. Neat little kit. Not the most precise generator out there but it's useful.
https://www.amazon.com/KKmoon-Precision-Generator-Adjustable-Frequency/dp/B01HM70CMY/ref=mp_s_a_1_2?ie=UTF8&qid=1524886358&sr=8-2-spons&pi=AC_SX236_SY340_FMwebp_QL65&keywords=xr2206+function+generator&psc=1

This.. I have really been enjoying look mum's cem 3340 tutorial:
https://www.lookmumnocomputer.com/cem-3340-diy-simple/

I would strongly suggest getting a resistor and capacitor kit off ebay or amazon.. They're like 15$-20$ each. That will get you a few of a huge range of resistors and caps:

https://www.amazon.com/Top-cofrLD-Resistors-1640pcs-resistors-Assortment/dp/B00WE1FQ8Y/ref=sr_1_14?s=industrial&ie=UTF8&qid=1541720878&sr=1-14&keywords=resistor+book

https://www.amazon.com/Joe-Knows-Electronics-Value-Capacitor/dp/B007SVHFXO/ref=sr_1_5?s=industrial&ie=UTF8&qid=1541720924&sr=1-5&keywords=capacitor+kit&dpID=41%252BFAHpNRVL&preST=_SX342_QL70_&dpSrc=srch

The worst part of these projects is waiting for parts. So Building up a little surplus of this kind of stuff will make your wait time much lower..

Oh yeah, of course it needs AC. I bought this earlier as an on/off switch for the power, does that mean it won't work?

I've seen that video more times than I can count trying to figure out some of these details that he either skipped over or I'm too much of a novice to understand. Thanks for the reply pal!

(1) buy a breadboard starter kit, battery/power supply, audio sockets, 10K, 100K, 1M potentiometers, a set of leaded resistors and capacitors, and a few diodes.

e.g. something like this: https://www.amazon.co.uk/ELEGOO-Electronics-Potentiometer-tie-points-Breadboard/dp/B01LZRV539/ will provide most of what you need.

You'll need to buy potentiometers as well. e.g. http://futurlec.com/PotRot.shtml

(2) buy a few CD40106 "Hex Schmitt triggers" - these are the core of your square wave oscillators. Each chip gives you 6 oscillators. More than enough for a drone.

http://www.ti.com/product/CD40106B?keyMatch=CD40106&tisearch=Search-EN-Products.

http://www.ti.com/lit/ds/symlink/cd40106b.pdf

They are common and cheap, and you can run them from 3V to 18V (absolute maximum)

(3) Read and build this http://www.fluxmonkey.com/electronoize/40106Oscillator.htm, and that will start you off.

(4) Start addings LEDs to the outputs of your oscillators so you can see what's happening in your circuit.

(5) Advanced: learn how to use op-amps, so you can do proper mixing, low/high pass filters, etc. These are usually "cookbook" circuits. Just learn how to make a few, and repeat them.

That's pretty neat. I wonder how well this one works now that I'm looking around. There are professional made knobs that reduce as well, but they're pricy!.

I few months ago, I bought some of these: https://www.amazon.com/gp/product/B008GXU43G

and now all of my drawers look like this: https://i.imgur.com/lnXoG57.jpg

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