
Resources for electronic engineers and hobbyists - kasbah
https://github.com/monostable/awesome-electronics
======
brandmeyer
A couple of things to add:

TI's Opamps for Everyone goes into great detail on various opamp circuits and
their design criteria.

If you have a mind for designing your own filters, GNU Octave's signal and
controls packages more or less replicate commercial Matlab's controls and
signal processing toolboxes (console mode only, of course).

LTSpice is a free SPICE with built-in schematic capture. It is very much tuned
for selling Linear's catalog, since it contains models for many of their
parts, but is also generally useful.

~~~
kasbah
LTSpice is already on the list!

Have started reading over the TI book:
[http://web.mit.edu/6.101/www/reference/op_amps_everyone.pdf](http://web.mit.edu/6.101/www/reference/op_amps_everyone.pdf)

Do you have a link or more info on working with Octave in this way?

~~~
brandmeyer
Any introductory text on SISO (single input/single output) control theory will
be a good start, since the same underlying tools are used for signal
processing as well as active control systems. The Wikibook on control systems
is OK, and will at least get you a feel for some of the mathematics. Modern
Control Systems by Dorf and Bishop is a great SISO textbook. Modern Control
Theory by Brogan is a great MIMO (multi-input/multi-output) text, too.

For just noodling and doodling around, the functions 'tf', 'ss', 'bode',
'freqz', 'butter', 'tf2sos', 'besself', and 'c2d' are a decent start.

[https://ccrma.stanford.edu/~jos/filters/filters.html](https://ccrma.stanford.edu/~jos/filters/filters.html)
and [http://dspguide.com/](http://dspguide.com/) are great online references
for digital signal processing, and you'll find that many of the underlying
mathematical tools for discrete-time analysis carry over into the continuous
domain, too.

------
brandmeyer
A few more for PCB work:

For prototyping work in the US, I've used
[http://ohararp.com/stencils/](http://ohararp.com/stencils/) for laser-cut
Kapton stencils, and [https://oshpark.com/](https://oshpark.com/) for PCBs.

For professional turn-key work in the US, I've found Advanced Assembly
([http://aa-pcbassembly.com/](http://aa-pcbassembly.com/)) to be absolutely
fantastic. They've managed to produce a pick-n-place automated process for
low-volume fully-assembled prototype quantity PCB _assemblies_. The service is
priced a little too high for amateur work, but its worth every penny for
nimble startup work.

~~~
antoniuschan99
How are pcbassembly compared to chinese fabs like SeeedStudio? Their prices
are cheap and they do fast turnaround.

~~~
Leoooeee
[https://www.seeedstudio.com/fusion_pcb.html](https://www.seeedstudio.com/fusion_pcb.html)

------
anfractuosity
I found
[https://www.snapeda.com/instapart/](https://www.snapeda.com/instapart/)
recently.

I just requested a part via their free plan, as I've never made a footprint
for a part before (something which I do need to learn).

I'd be interested to know of other people's experience with them.

Also I found [http://pcbshopper.com/](http://pcbshopper.com/) pretty handy.

~~~
kasbah
Yes, PCBshopper.com is really nice and I forgot about it!

There is a PR open for SnapEDA but I am a bit reluctant as I don't have enough
experience with using it. If you jump in on that I might change my mind:
[https://github.com/monostable/awesome-
electronics/pull/1](https://github.com/monostable/awesome-electronics/pull/1)

~~~
teaBOT
Great list! Thank you! I agree with @anfractuosity, that I'd like to see
SnapEDA on this list. There my go-to source for CAD packages. I don't even
create CAD parts anymore; if it's not in their DB already, I just request it.
I've had great success with them.

------
donquichotte
Nice list! I also recommend "The Art of Electronics" by Horowitz and Hill. It
is quite encyclopedic, but often very clear and well illustrated.

~~~
Animats
Yes. The Third Edition came out last year, after a delay of about 20 years,
and now they're up to date. This matters, because they mention lots of
specific part numbers.

Horowitz and Hill haven't accepted that everything is surface mount now. Read
their chapter on soldering, where they whine about surface mount, instead of
telling you how to do it. There are lots of surface mount soldering videos,
most of which are by people who have much better than average tweezer
dexterity.

~~~
TaylorAlexander
That's unfortunate about the surface mount.

As a word of encouragement, I know one can do complex surface mount soldering
with just a few specialized tools.

I picked up a good stereo zoom microscope from craigslist. Mine is a Leica but
I also recommend the amscope and similar models you can get online. They're a
chinese rebrand but I've used those models and the optical quality is great. I
recommend the models with a boom arm if you have the space.

Then you need a hot air rework station.

You can apply solder paste manually from a tube - just squirt the paste onto
the pads. This is uneven and will require clean up with an iron and sometimes
multiple tries.

Get a no clean flux pen also.

If you want to do more than one PCB, I highly recommend using a solder
stencil. I recommend getting PCBs from Seeed studio in china - 10 PCBs starts
at $20 (total) plus shipping (around $40). Throw in a solder stencil for
another $20. When the stencil arrives use heavy scissors to cut out about two
inches/50mm around your design, take one of the pieces of stiff board that the
PCBs are packaged with, tape down some extra PCBs around one free PCB, and
then tape the stencil on the top so it lines up.

Get some solder paste from Digikey or Sparkfun and use an old gift card to
squeegee it onto the PCB. Then lift the stencil up using one piece of tape as
a hinge. Super easy to do this at home.

Now place on parts using tweezers and the microscope.

Then use the hot air gun to slowly heat up the PCB till it's all about 260C,
and then turn it to 360C and briefly melt the solder at all locations. Then
let it cool.

If you want to do this regularly, invest in a T962A soldering oven from ebay
for ~$300 from ebay.

I did a kickstarter for a little wireless internet of things board, and this
is my process for home assembly. When you want to do mass assembly, consider
Seeed studio. I had them assemble 4000+ boards and it mostly went well. I did
have an issue with an incorrectly substituted part so be very clear about what
work you expect done and be clear about which parts you will accept
substitutes for. They did make good on their error and I would use them again.

My email is in my profile if you want more tips on SMT soldering.

For reference, here are two board that I soldered using the above techniques:
[http://www.tlalexander.com/content/images/2016/07/IMG_6493_e...](http://www.tlalexander.com/content/images/2016/07/IMG_6493_edited_sm.jpg)
[http://www.tlalexander.com/content/images/2017/01/IMG_7344_e...](http://www.tlalexander.com/content/images/2017/01/IMG_7344_edited_sm.JPG)

EDIT: For PCB design I previously would have recommended EAGLE, but now I
would recommend KiCAD. I have not yet used KiCAD, but this is just a learning
curve issue (new software versus a busy schedule). If you're learning from
scratch and want a tool you can use forever, I'd recommend KiCAD based on
recommendations from others.

~~~
Animats
The T-962 and its clones out of the box have temperature so uneven that it can
scorch the center of a board while reflowing OK an inch away from the center.
With various mods [1] it's marginally usable. I've used TechShop's unmodified
clone unit (melted the solder mask at board center and scorched the FR4
substrate) and a used modified Puhui unit (after careful setting of a suitable
heating curve, acceptable.) With new firmware, the cooling fan is run slowly
during the heating phase, which stirs the hot air and reduces the hot spot
problem. You have to pay about $3000 to get a reflow oven that Just Works,
unfortunately. The good ones are true convection ovens with uniform air
temperature.

KiCAD is not bad. The schematic drawing part is mostly OK. The schematic
symbol and footprint editors are poor draw programs, and the library
management is painful, but once you figure out all the quirks, usable.

Board layout is strange. There are really two board layout programs, one for
OpenGL and one for non-OpenGL, and they have different features, some of which
are completely irrelevant to the display. You can switch back and forth on the
fly. There used to be an auto-router, but due to an IP problem (the author of
the auto-router worked for a company that sold auto-routers) it's been
deprecated. Manual routing has a lot of computer assistance, and is usable but
touchy. The output end, with Gerber and drill files, seems to work fine; I've
had boards fabbed by two vendors with no problems.

[1]
[https://github.com/UnifiedEngineering/T-962-improvements](https://github.com/UnifiedEngineering/T-962-improvements)

~~~
abakker
If you are already making your own PCBs, making your own kiln with a
thermocouple, PID, and heating element ought to be no sweat. Just buy a
handful of softbricks, cut them with a saw, and put them together. I've made
kilns like this that go up to 1950F. 300 - 400 should be really easy.

~~~
Animats
It's not about getting it hot enough.

Surface mount soldering requires a careful temperature profile. You first
preheat to about 50C below the melting point of solder for about two minutes.
Then, the temperature is raised to above the reflow point and held there for
about 20 seconds, which is when the soldering takes place. It's easy to damage
the components at this point; many components have a maximum temperature
tolerance of only 30 seconds at reflow temperature.[1] Then there's a cool-
down period. There are ramp rate limitations - heating up too fast causes
solvent "pops" in the flux, and heating up too slowly cooks the components.
Cooling too fast causes cracks in the solder; cooling too slowly cooks the
components. A brick kiln would have too much thermal mass for all those
controlled temperature changes.

Once it's all tuned and controlled properly, it works great as a cheap
production process. The commercial systems work like a hamburger cooker at
Burger King - there's a chain conveyor and several zones of different
temperature through which the product passes. Once one of those ovens is
warmed up and stabilized, it produces consistent results. It's doing this on
one-offs that's hard.

Leaded soldering is about 2x more tolerant of temperature variations than
lead-free.

[1]
[http://www.latticesemi.com/~/media/LatticeSemi/Documents/App...](http://www.latticesemi.com/~/media/LatticeSemi/Documents/ApplicationNotes/PT/SolderReflowGuideforSurfaceMountDevices.pdf?document_id=8902)

------
compumike
[https://www.circuithub.com/](https://www.circuithub.com/) for short-run turn-
key manufacturing (hobbyist friendly at small quantities)

[https://www.circuitlab.com/](https://www.circuitlab.com/) for browser-based
circuit simulation and schematic capture (now used for teaching EE in dozens
of US universities and growing -- note: wrote it!)

[http://electronics.stackexchange.com/](http://electronics.stackexchange.com/)
for Q&A, beginner to intermediate level topics

------
madengr
Electrical vs electronics engineering is also differentiated by those who take
electromagnetics, thermodynamics, and those who don't.

Perhaps there is too much to pack in, especially since EE is often merged with
the CS department, but students are getting off too easy these days.

------
gjkood
Wow, this is a very good list and eminently bookmark worthy.

I would also include sites like Adafruit.com and Sparkfun.com for prototyping
supplies and the blogs they host. I know Octopart or the other Parts searches
would cover these.

Another useful link would be to lists of electronics tools/instrumentation
such as Oscilloscopes, Logic Analyzers, Spectrum Analyzers, plain vanilla
Multimeters. EEVBlog has fantastic blog posts/equipment reviews and is already
included in the list. This would help build your own little electronics
workshop and would be useful to folks who are not formally trained in EE and
want to self study and practice.

I especially loved the 'All About Circuits' tutorial site. I am too lazy to
pore over my old Millman & Halkias or Horowitz and Hill text books. This gives
me the information in bite-sized chunks.

Edit: I just noticed the 'contributing.md' link. Good work. "Don't come to me
with problems, come to me with solutions." eh?

~~~
Etheryte
Seconding your instrumentation post, I always have a very hard time when I
need to buy a new tool, a simple up-to-date guide would be super helpful.

------
dthal
This listing seems to be missing
[https://upverter.com/](https://upverter.com/).

------
jwr
I would like to shamelessly submit PartsBox.io
([https://partsbox.io/](https://partsbox.io/)) as a solution to keep track of
your components once you start designing & building something.

It's free for Hobbyists/Makers with single-user access, multi-user access is
in paid plans.

(I'm the founder/creator)

~~~
kasbah
Hi jwr, I have been considering adding a section with Partsbox.io and
Partkeepr but have been hesitating because I don't have any personal
experience with them yet. But given I got this review from a redditor I should
probably add it:
[https://www.reddit.com/r/electronics/comments/5oc84d/a_curat...](https://www.reddit.com/r/electronics/comments/5oc84d/a_curated_list_for_awesome_resources_for/dciobw4/?context=3&st=iyhm2b2m&sh=41599414)

On a side note I would love to pick your brain sometime about starting a
business in this area as I am considering the avenues for turning my project
sharing site [https://kitnic.it](https://kitnic.it) into one.

~~~
jwr
Well, try it your self and see if you like it :-)

As for brain picking, no problem, please contact me directly — I will gladly
talk to a fellow entrepreneur.

~~~
kasbah
I _have_ checked out the web interface a bit and it seemed really nice. I
think the main problem for me is the time investment required to input all the
parts to give it a real go.

Will be in touch soon about the business side.

------
kasbah
If anyone hear could vouch for Qucs simulator and explain a bit why it's good
I would love to add it. It was recommended before but without reasoning and I
haven't had a chance to try it.

[http://qucs.sourceforge.net/](http://qucs.sourceforge.net/)

~~~
blackguardx
Qucs is trying to emulate Keysight's ADS software. It is mainly RF focused,
but can do a lot more. ADS is awesome. Qucs has great potential, but needs
some work. It is still useful, though.

