(Part 2) Best products from r/AskElectronics

> Answer for New to electronics, where to start?

Everybody learns differently. Some people are theoretical learners, while others are physical learners who need to touch things with their hands to learn anything. And others still are some hybrid between the two. As such, it is very difficult to answer the question "where to start", because there is no one-size fits all solution.

Further complicating the issue is the issue of budget. Not just monetary investment, but time investment as well. No doubt, the best education possible is to simply go to a multi-year university and dedicated multiple years of your life to the trade, but this is more than the typical hobbyist can afford.

Assuming infinite time and money, the ideal learning environment is a lab environment surrounded by high-end, precise and accurate equipment (often costing in the thousands of dollars) with which you can measure, test, and experiment to the heart's desire. For example, accurate variable power supplies that can operate in voltage-mode or current-mode... signal generators to create square, triangle, and sine waves, and a high-end, very accurate Tektronix Oscilloscope so that you can actually see the voltages and currents as they happen. Indeed, this is what your typical lab environment inside a college would be like.

Dedicate yourself to graduate-level college subjects, and you will also get you access to very high-end material, such as scanning electron microscopes, clean-rooms, VLSI integrated circuits, FPGAs and custom PCBs to tie it all together. Mastery of these subjects, aided with state-of-the-art software for simulations will put you into the upper-echleons of world-class electrical engineering.

But learning how to use such complicated equipment is itself a learning curve that takes not only money... but time as well. There are plenty of hobby-level electronics users who make due with both simpler and cheaper equipment.

AA or 9V Batteries provide cheap sources of nearly ideal voltage sources (at least, while the batteries have juice in them). Digital Multimeters can be bought as cheaply as $20... although most people will recommend spending around $100 for a solid precise and accurate multimeter (better accuracy costs more money). Add on $50 to $100 for a breadboard and some typical components (a light bulb, a motor, resistors, capacitors, and some basic chips like a 555 timer or an Op-Amp, and wires to hook it all together), and you'll be well on your way to learning electronics.

Finally, there's the issue of subject material. There are complicated analog components, like building power-supplies, or radios... and then there are complicated digital components like logic and even computers. The two worlds require different math to understand (Discrete mathematics for Digital, Calc3 / Differential Equations for Analog).

There are also software packages to help students learn on the cheap. There are programs that are free for hobbyists, like LTSpice for simulations or Eagle for schematic drawings / PCB layout.

--------

I'm sorry for the long-winded answer, but this is a deep subject with many valid paths forward. This all comes down to the following:

1. You need to learn some degree of theory to get started.
   
   
2. You can accelerate and/or augment your theoretical learning with software tools such as PSpice. Its a lot cheaper and faster to simulate an effect rather than to actually use real components.
   
   
3. You need physical equipment. Software will never replicate the smell of burning components when that resistor catches on fire for the first time. Some things can only be learned when working in the lab.
   
   Theory
   ============
   
   Here are a list of recommended books:
   (Someone else: make a list of good beginner books, I dunno of any).
   
   There are also free online courses:
   
   

• MIT's 6.002: This is the first course taught at MIT, and all of the video lectures, exams, and class material has been posted online for free.
  
  
• All About Circuits: This messy webpage actually holds a lot of good information about circuits and electronics. I find that paid books are better, but if you don't want to spend any money, this is a very complete reference.
  
  Software
  ===========
  
  The primary software you need as a beginner is a "SPICE" simulator. You can place components like resistors, capacitors and inductors and the software will simulate the components.
  
  
• Partsim is a free website that can simulate your basic electrical components.
  
  
• LTspice: Linear Technology wants you to buy their stuff, so they made a free program that accurately simulates their chips. Can't argue with the results or this marketing scheme though, free software is extremely good and useful for the beginner.
  
  Tools and Hardware
  ===========
  
  
• Uggghhhh. I'm tired. Work in progress, will continue writing later.
  
  
  WORK IN PROGRESS
  ==============
  
  
• Finish First Draft
  
• Edit down my wordy language to be shorter
  
• Come up with good beginner books (paid books generally are easier to read and are better edited)
  
• Figure out some decent beginner kits: both digital world (something Arduino based with a decent free web-lessons), and analog world (opamps and stuff).
  
• Work out a set of beginner tools, in order of "cost-effectiveness" (Ex: Digital Multimeter, cheap USB Oscilloscope, etc. etc.)

Way back when dinosaurs roamed the Earth and I was a young fella, I forget how old but probably pre-teen, my parents bought me something like this: http://www.amazon.com/Elenco-200-in-One-Electronic-Project-Lab/dp/B0002AHR04 To make a circuit, you'd just bend back a spring and shove a wire in between the coils. Looking at the "related products" on Amazon, it seems like there are a few competitive products out there too. The kit my parents got me kept me entertained for a very long time. This was possibly enhanced by my father who, being an electrical engineer, would periodically involve me fixing broken appliances, handing me the sledge to help tear down walls during renovations and whatnot.

This kit taught me the basics of flip-flops (which can be used to MAKE NOISE! as well as flash lights), relays etc.

---

My current flight of fancy is the Arduino and that may prove a more useful tool for you because it can all be done with low voltage, a bread board and a bunch of wires and even better, it needs a computer to program it. The Arduino IDE includes a whole bunch of example programs.

The most basic program is "flash" which just literally flashes an LED. Your next step would be to alter the duty cycle of the flashing. Now have it flash two LEDs and have them on different duty cycles.

A Chinese Arudino UNO clone Starter Kit (which in addition to some basic components and a breadboard includes a stepper motor, servo, tilt switches and other cool things) will set you back less than $50. Additional wires (I recommend getting a pack each of M-M, M-F and F-M dupont leads) are cheap as chips and will help you hook up all the other awesome things you can get like the "arduino sensor kit" which contains no less than 37 different kinds of "sensors" including ultrasonic range sensors, joysticks, push buttons, etc.

Armed with those two kids, a bunch of wires and a laptop running the Arduino IDE, there's a whole world of awesome to play with.

Show me pre-teen who wouldn't like an ultrasonic alarm pointed at her door to make a buzzer ring when mum opens the door, and I'll show you a kid who... is too engrossed in a book to notice. (OK, so my analogies aren't always top notch)

This only deals with receiving, not transmitting, but I've heard good things about the book Build Your Own Transistor Radios: A Hobbyist's Guide to High-Performance and Low-Powered Radio Circuits.

Here's the description from Amazon:

--------
A DIY guide to designing and building transistor radios

Create sophisticated transistor radios that are inexpensive yet highly efficient. Build Your Own Transistor Radios: A Hobbyist’s Guide to High-Performance and Low-Powered Radio Circuits offers complete projects with detailed schematics and insights on how the radios were designed. Learn how to choose components, construct the different types of radios, and troubleshoot your work. Digging deeper, this practical resource shows you how to engineer innovative devices by experimenting with and radically improving existing designs.

Build Your Own Transistor Radios covers:

• Calibration tools and test generators
• TRF, regenerative, and reflex radios
• Basic and advanced superheterodyne radios
• Coil-less and software-defined radios
• Transistor and differential-pair oscillators
• Filter and amplifier design techniques
• Sampling theory and sampling mixers
• In-phase, quadrature, and AM broadcast signals
• Resonant, detector, and AVC circuits
• Image rejection and noise analysis methods

This is the perfect guide for electronics hobbyists and students who want to delve deeper into the topic of radio.

As a student, I can recommend "Practical Electronics For Inventors, Fourth Edition" by Paul Scherz, accompanied by the occasional youtube video and reddit question :)
You can buy it from Amazon here

I havent read any others, so I cant compare the quality, but you can go through it like a book and be able to understand everything. You may run into some problems in the real world that requires some fairly advanced calculus, which the book doesn't cover. (It does cover where to apply it, just not how). It is really extensive (1256 pages on my desktop e-reader), so if you have an idea for something specific you want to build, there might be something more efficient out there :)

I would think that not a lot of electronics books, if any, explain the math in full, so I would suggest that you find an online source for whatever specific piece of math you've run into. I can recommend Kahn academy.

Good luck :)

Not very. That crimper is made specifically for the PicoBlade series connectors from Molex. And at that, only one pitch of PicoBlade connectors (there are multiples) It will not work with all terminals in that range. Well, it might or might not but it's really a crapshoot. Molex crimpers are generally made for a specific set of terminals for a specific pitch for a specific connector series, and are not intended to be universal. Not sure if Molex offers interchangeable dies either, although I assume they would. BUT not all of their terminals use this style of crimper either. Some have entirely different form factors with different types of dies.

Also, if you haven't used a Molex crimper they have a spring-loaded button thing on the back that pushes a plastic piece forward between the open die, which holds the terminals. Check out this video. They are not universal either and each is designed for a narrow range of terminals. Molex makes dozens of different crimpers. You can fit other terminals in there sometimes but they won't hold well and will be too wobbly or too big. Some of the terminals require unique finished crimp geometries to fit in the connector housing, and so crimpers for them won't work well for "general purpose" terminals.

I recommend staying away from the OEM crimpers - as nice as they are - until you have a specific need for one or you need to assemble a ton of connectors. If you're putting connectors in something mission-critical or very hard to get to, it may be worth it to get the correct OEM crimper to ensure crimp quality. For most hobbyist purposes though - not worth it IMHO.

Instead, I'd suggest picking up one of these. So far I like it a lot more than the "engineer" crimper which I've also used extensively. The IWISS is actually a "combo" of 2 of their other crimpers and covers a pretty wide range of terminals. It will also crimp both wire and insulation in one step, and the die is sized differently for those portions. Much more convenient, twice as fast to do a terminal. The Engineer crimper requires you to first crimp the wire, then the insulation (or vice versa).

The engineer is OK but it's not nearly as good for small terminals. The clearances inside the closed die are quite large, terminals get jammed in there and misshapen or broken. Or the part sticking out of the die is bent by the crimping process. It's also not correctly toleranced for insulation crimping so you have to do it by feel or you'll just crimp through the insulation altogether. I've pretty much decommissioned that one. The IWISS has so far been very good, just squeeze all the way and done with good insulation crimping.

Of course, if you know you will only use that series of connectors and you don't mind the outlay for OEM crimpers, then by all means go for it. They are super nice to use so if you can justify it then more power to you!

Alright, you and /u/PioneerStandard have convinced me.

Would you mind helping me figure out which would work best?

Would a ratcheting one like this be best despite the cost? https://www.amazon.ca/Titan-11477-Ratcheting-Terminal-Crimper/dp/B0069TRKJ0

Or would a nice/decent wire stripper/cutter/crimper like this work alright? https://www.amazon.ca/Gardner-Bender-GS-366-Multi-Purpose-Crimp/dp/B00164C0KW

Also, would a more "plier-type" tool work as well? https://www.amazon.ca/Irwin-Industrial-2078309-Stripper-ProTouch/dp/B000JNNWQ2

Thanks by the way.

Oh that's great, thank you. I may take you up on that one of these days. I grabbed a chinese starter kit (this) off Amazon and a multimeter tonight (this). I've been wanting to get into this for years. I'm already a developer, the electronicy bits just elude me and I can't stand it anymore, I feel like I'd excel at this and I always have ideas I can't execute on without the knowledge. I'm 37 but your high school level material is just what I need at the moment.. haha.

I chose the kit to keep the cost down and learn the basics. Need to start budgeting my hobbies better. But if there's anything that would be a big benefit to have in addition, I'm all ears

It looks like you have a decent soldering station, that is really the main thing. You'll need a small tip, but probably not as small as you think. I like the Weller ETL, but a ~2mm screwdriver style tip works well for SMD in my experience. If you go too small it can actually cause trouble for heat transfer and thermal recovery.

If you've mostly been doing through-hole stuff, you'll want smaller solder. Having small diameter solder makes it easier to feed just the right amount. I like Kester 0.020, some people go even smaller. Of course there are lead-free versions of that, too, if you prefer.

For through-hole, the flux that is inside the solder is usually enough, but for surface mount, you'll need extra flux. You'll probably be fine with a flux pen. You'll probably want some solder wick because mistakes happen, and a solder sucker thingie doesn't work as well with surface mount.

As u/t_Lancer says, you won't need a hot air station and solder paste unless you're planning on doing leadless packages. If you decide to get a hot air station, though, they're pretty cheap. You don't even strictly need solder paste, I've been making do by tinning the pads with regular solder first with my soldering iron before hitting it with the hot air.

For vision, it depends on how your eyesight is. I'm fine eyeballing down to 0603 but I can't read the markings without help. I've started doing all of my soldering under light magnification with the Optivisor DA-3 with a LED attachment which has really helped, but it isn't strictly necessary. You can get those visors with more magnification at the cost of a shorter working distance. Good room lighting and a magnifying glass work fine, too.

And most important thing you need is practice. Watch this video and grab one or two of those SMD practice kits and you'll be knocking out surface mount stuff in no time.

To drive one of those LEDs from a 9V battery you are going to need a series resistor for current limiting. The lower the resistance, the higher the current and the brighter the LED (and the faster you run down your battery). The higher the resistance, the lower the current and the dimmer the LED (and longer battery life).

I suggest you experiment on your kitchen table with various resistors and find the one which gives the brightness YOU require. In the Joe Knows Electronics resistor kit (amazon link), try 330 ohms, 390 ohms, 470, 560, 680, and 820 ohms. See which one YOU like. Then after you've picked a resistor value, consider that to be your "final circuit design". Build it into its permanent enclosure and hope you don't change your mind later.

Could you do this with a variable resistor and thereby, have a knob on your gizmo that lets you change the brightness whenever you like? Yes. Yes you could.

I had the same approach as you when I first started learning electronics; I'd recommend Practical Electronics for Inventors. While it does explain just about every topic in great detail, it does so at a pace that's neither too slow nor too fast; you can easily skip the more technical chapters, and stick to the easy bits too.
However, if you want to do more than create simple signal clipping distortion pedals, I would suggest that you read the technical stuff as well, to learn what actually goes on in a circuit, and to understand how you might modulate your guitar's sound.

This is a project from someone in 2002

http://xoscope.sourceforge.net/hardware/hardware.html

https://www.instructables.com/id/Simple-PC-oscilliscope/

http://www.yann.com/en/diy-turn-your-gnulinux-computer-into-a-free-oscilloscope-29/09/2010.html#comment-2150581

I searched xoscope for the project I heard about. But for keep in mind this project is limited to the audio technology in it, in other words limited voltage and frequency.

a more direct answer, I searched "input voltage on computer microphone"

and I choose this link http://www.glenalec.net/projects/pcmic/

An alternate solution is to buy a kit like:

https://www.amazon.com/Elenco-Multimeter-SOLDERING-ASSEMBLY-REQUIRED/dp/B0002HDTEA/ref=sr_1_2?keywords=diy+multimeter+kit&qid=1574887642&sr=8-2

A book that I liked when I was getting started in electronics are from Radio Shack and I doubt they are sold any more:

• "Getting Started In Electronics" by Forrest M. Mims III ( the 2003 version looks like the 1983 version the one I had)
  
• "Engineer's Notebook 1" (Radio Shack, 1979) by Forrest M. Mims III
  
• Engineer's Notebook 2" (Radio Shack, 1982) by Forrest M. Mims III
  
• and many more, some of mini note books and lots that Radio Shack sold a long time ago.
  
  Forrest M. Mims III link http://www.forrestmims.org/publications.html
  
  What I like is the practical explanation of volts, current, resistance and the electronic Law's like Ohm's Law, Watts Law and so on. The practical explanation of the discrete components too, like resistors, capacitors, diagram symbols and more . . . If you choose to look and get some you will really appreciate the concept of number of transistor in a CPU.
  
  [edit] just read some of the posts after posting, link https://www.nicomania.de/ipod/oszilloskop-tastkopf-fuer-ipod-iphone-und-android
  
  about using iphone or android phone for an oscilloscope

obviously checking a wall outlet for power is useful (AC volts). depending on how much you debug house electronics, resistance measurements can be useful.

​

I really like the amprobe AM-510 because it has a couple features that cheaper meters don't, and it's only slightly more expensive. the two best features that are beyond the cheap ones:

1. proximity voltage detection for AC wiring. you can hold the meter up to a piece of romex/house wiring and it will beep if it's hot. sometimes works on fixtures and light switches while the cover is still on, but I wouldn't count on it.
   
2. capacitance measurement. if you want to repair something, or test to see if your furnace start-up cap is still good, you can measure it. cheap ones often don't do cap measurement well or at all.
   
   https://www.amazon.com/Amprobe-AM-510-Commercial-Residential-Non-Contact/dp/B007FZFTZO/ref=sr_1_3?keywords=AM-510&qid=1563921229&s=industrial&sr=1-3

It'll be blackened, solder won't stick to it, and it'll have poor heat transfer.

Properly tinning and caring for your tips is one of the first things you should learn--use the bronze puff (or less ideal sponge) to clean off flux and excess solder during use.

If it's a good quality tip, the black stuff will only be burnt on flux, rather than full oxidation of the cladding (at which point, you should replace it). To quote myself from another post (n.b. don't use sand paper to try to clean up your tips):

> I use a scour pad (keep a small part of one in your toolbox, inside a ziplock) on my tip when it gets really carbonized, and then follow it up with Weller tip tinner / activator. As many others are saying here, a low-abrasive bronze puff is better than a damp sponge for cleaning your iron when in use, since it can better wick solder and doesn't subject the tip to as much thermal stress.

To follow up on what the above user said, I bought the Elegoo Arduino UNO kit on Amazon, the whole kit costs less than most official Arduino UNO units and this specific kit comes with a whole bunch of micro controller projects on a cd and the relevant components to complete them with enough spare components to experiment with.

I’ve actually since bought a second one because I felt like it was good value. Hope this helps!

did you get a kit?

i'm interested in some basic audio and control circuitry testing.

for the audio i really only need to be able to see if there's clipping or significant distortion compared to the output of a known well performing amp.

for the control it's even simpler, i just want to be able to monitor voltage being applied to some terminals in real-time, but my multimeter is insufficient to track 4 outputs with momentary voltage.

do you think these kits would be a better option than something like a cheap Hanatek scope?

https://www.amazon.com/Hantek-HT6022BE20Mhz-Digital-Oscilloscope-Bandwidth/dp/B009H4AYII/

1. YouTube - Online. Take advantage of it. When I first started learning about electronics as a kid, there was no such thing as home computers or the internet.
   
   
2. Google - Online. If you don't understand something, then ask google. Download datasheets. Two more things I wish I had way back in the day.
   
   
3. Wikipedia - Online. Great for some electronics topics, but it varies from topic to topic.
   
   
4. Books - Online.
   
   

• Engineer's Mini Notebooks (booklets)
  
  
• Lessons In Electric Circuits (2700 pages)
  
  
• Electricity & Electronics Training (modules)
  
  

5. Books - Printed. Buy at least one or two starter books.
   
   

• Make: Electronics (get 2nd edition)
  
  
• Make: More Electronics
  
  

6. Historical Electronics Magazines - online. When I was young, I had subscriptions to multiple electronics magazines. It was one of the best ways to learn a hobby before the internet existed.
   
   

• Popular Electronics (PDF archive)
  
  
• Radio Electronics (PDF archive)
  
  

7. Electronics Magazines - Printed (or PDF):
   
   

• Circuit Cellar
  
  
• Elektor Electronics
  
  
• Everyday Practical Electronics
  
  
• Nuts & Volts
  

Thanks, this is very helpful. I think I'll go for something like this asssuming they're not lying about it being regulated, just for simplicity's sake and b/c I'll need a few of them. Even better, would 3.2v be too much? Reviewers are saying the voltage is 3.2v with or without a load for that adapter.

Also, How would I go about making a power supply that would work in series for 2 units? [unit][unit]{wall}

Do I just buy a 5v-6v adapter or will it not displace the current properly?

I'll just give you a list of the items I've been using (and like):

https://www.amazon.com/Hakko-T18-D08-D12-D24-D32/dp/B00C1N30DI Hakko FX-888D. The extra tips may be unnecessary, I only ever use the one chisel tip

https://www.amazon.com/gp/product/B00068IJPO Leaded solder

https://www.amazon.com/gp/product/B004SPGFT8 Brushes

https://www.amazon.com/gp/product/B00FZPDG1K Side cutters

https://www.amazon.com/gp/product/B00425FUW2 Flux

https://www.amazon.com/gp/product/B008O9VLA2 Solder Wick

https://www.amazon.com/gp/product/B0013HT2QW KimWipes

https://www.amazon.com/gp/product/B001B5JT8C Isopropyl Alcohol

https://www.amazon.com/gp/product/B005CU56KM Acetone spray (use carefully/sparingly)

https://www.amazon.com/gp/product/B004G5T9M0 Jewelers loupe

https://www.amazon.com/gp/product/B019SLLOMY Tweezers

https://www.amazon.com/gp/product/B00P8Z4RPG Hot air station (works well despite Chinesium)

Also, I noticed in Dave's videos he rarely adds flux, just the flux that's built into the multicore solder. I don't know if I'm alone on this one but with flux I always felt the bigger the glob the better the job. Just have to clean it afterwards with the solvent, tissues & brushes.

Edit: Okay that's a much bigger list than I thought, this stuff can get expensive!

Yes. Ronald Quan's (book on homemade radios) advocates the dirt cheap LM318 opamp, available from electronics surplus stores, hobbyist websites (example), and even legitimate electronics distributors like Arrow, Element 14, Mouser, and DigiKey. Its gain-bandwidth product is 15 MHz so the OP can use one to construct a preamp with a gain of +30dB (31.6x) for 0.125 MHz input signals. Need more than +30dB of gain? Cascade two of them!

These Titan crimper are pretty great,

https://www.amazon.com/Titan-Tools-11477-Ratcheting-Terminal/dp/B0069TRKJ0

I use panduit brand crimpers at work that they pay close to $1000 for, these are every bit as good in my opinion and they are $25

Yeah I think that kit would be a little too basic for an 18yr old. Ok but you will quickly outgrow it.

I'd get an Arduino Uno starter kit instead. Uno are plenty advanced to do lots of fun projects. The Mega 2560 kit Ox linked is bit more than you would need.

I typically use 60 40 0.031 lead solder, which is cheaply available from amazon, including prime. One of these spools will last a very long time for only $30. These tubes are available for smaller quantities.

The main concern with solder is the flux fumes, which are actually worse with higher temperatures and lead free solder. One simple solution to solder fumes is a pc fan with some sort of filter on it, such as this one. I made one for around $4, and it works very well. It also helps to mount it on some sort of arm, such as solid copper wire or one of these. There are many types of fume extractors that would work.

As for the soldering iron, I use a weller wes51, but a hakko fx888 is also good.

Bit more than you probaly want to spend, but I've had good luck with this one for about $90. Korad kd3005D

You don't want a voltage divider, that's a pretty specific circuit made out of resistors ;)

I've found these little devices pretty handy for running things off a 12V supply. They're limited to 3A, but with a little bit of wiring you should be able to run them in parallel... tweak both of them to the exact same output voltage on your multimeter, then wire them up in parallel, throw a 100uF cap across the output leads to help filter the supply, check the voltage, and you're set. Once the rig is running to your satisfaction superglue the pot screws so they don't get turned accidentally.

Holy hell, you're amazing , I'm print a hold to Arduino to complete this learning process.
>
Edit: also, not even joking, maybe you can pick up one of these: https://www.amazon.com/Maxitronix-200-in-One-Electronic-Project-Lab/dp/B0002AHR04.

This is actually really amazing, how didn't i hear of it before?
Thank you so much man, you are using a lot of ways for me and lighting my way, Thank you

I just happen to have written a book about it!

But, if you tell me what kind of BMS (small battery, large, for what application), I may recommend the best book for your particular needs.

Here is the one that I use. It's heavy, but works pretty well for me.

Even a 9V will run out of juice eventually, unless you're talking rechargeable. You could also just buy rechargeable AAAs.

Back of the envelope calculations for average alkaline batteries - 9V batterries have ~5.085Wh, 3 AAA's have ~2.58Wh. To step 9V to 3.5V (3 AAAs in series), you'll have efficiency losses in the best case of ~80% with a buck regulator or 4.068Wh and the worst case with a linear regulator (3.5/9) = ~38.9% => 1.98Wh. So in the best case you'll get a 4.068/2.58 = ~1.58x increase in battery life with a 9V, for the added cost of a buck regulator.

The advice you were given was far more complex than you need.

Simply buy a 3vdc wall wart for $5 including shipping. Cut off the plug, and strip the leads. Connect the positive lead to every positive wire to the LED letters, and the negative lead to all the negatives. You could get away with twisting them all together and then taping, but soldering would be best. You could also crimp, use a wire nut, or use Wago push-in connectors. BAM, you're done.

Want to have it be switchable? Repurpose one of the switches from your letters. Simply cut the positive lead from the wall wart, and splice the switch in there. Or, you know, just unplug it.

To use a freakin' USB power supply and buck converters is ludicrous. Cancel your order.

https://www.amazon.com/Joe-Knows-Electronics-Value-Resistor/dp/B003UC4FSS/ref=mp_s_a_1_2_sspa?keywords=resistor+assortment+kit&qid=1573074991&sprefix=resistor&sr=8-2-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEyWE1WMVFCTEZKTjJZJmVuY3J5cHRlZElkPUEwNTk4MjU1MTlSRUhHTFdDWDZUMyZlbmNyeXB0ZWRBZElkPUEwMjY5NzI5Mk1BM0tKRFhPNzlMTCZ3aWRnZXROYW1lPXNwX3Bob25lX3NlYXJjaF9hdGYmYWN0aW9uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl

I trust you are capable of typing the word "breadboard" into Amazon's search bar yourself.

For scope: get a used tek on craigslist

For function generator: this kit

For iron: Hakko 888

You probably want a bench PSU as well: Korad 3005D

You need safety gear too!

• Respirator - half face with P100 filters
  
  
• Goggles
  
  
• Gloves
  
  Don't forget blank PCBs and etchant, breadboard, jumper wires, etc.

I'm not sure if I completely understand the zener regulators but it seems to me as though the power consumption of simple one is going to be wildly high with such a large difference between input and output voltages.

Perhaps if I can ensure the voltage does not jump too high and the current demands are low enough one of these switching regulators will work well: https://www.dimensionengineering.com/products/de-swadj3

Too bad they're fairly pricey.

Edit: Better yet something like this: http://www.amazon.com/RioRand-LM2596-Converter-1-23V-30V-Pcs-LM2596/dp/B008BHAOQO

The Engineer PA-09 is the only one worth having for those little guys. They have a thin jaw that works well on the really short-depth terminals, but this makes them annoying to use on larger (automotive and stuff) terminals.

For larger terminals (common "dupont" up to large automotive stuff), just get these and be done with it. They're the best and most universal I've found in yeeeears of horsing around with this stuff. Their jaw is too thick for the small JST stuff, however.

Those two crimpers cover 99% of the open-barrel terminals in the world, for roughly $100 combined.

This one.

Amazing book, in my opinion.

0.6 to 0.8 mm (0.031 inch)

Can't go wrong with kester 60/40. 63/37 is slightly better but 60/40 is fine.

https://www.amazon.com/KESTER-SOLDER-32117-24-6040-0027-Diameter/dp/B00068IJPO/ref=mp_s_a_1_6?keywords=solder&qid=1572723893&sr=8-6

Just so you know in the future, that doesn't look like the proper way to crimp those terminals. I'm guessing you just smashed them with a pair of pliers but you should always use the proper crimper on terminals like that when it matters because the wires can slip out.

You can probably get that model cheaper somewhere else, BTW. I just linked to the first place I could find it.

There are also even less expensive choices that are still quite good quality, though you won't get quite as much current. For example, buy two of these: http://www.amazon.com/KORAD-KD3005D-Precision-Adjustable-Regulated/dp/B00FPU6G4E/ref=pd_cp_hi_0/190-7609066-1491003

This thing is the most efficient way to do it

You just want a controllable constant-current-constant-voltage power supply. Buy this.

Your solenoids, like all DC loads, have some Current vs Voltage curve, that they have to obey. For the simplest load possible, a 1-ohm resistor, that curve is Current = Voltage / 1 Ohm. Solenoids might have a nonlinear curve. But they simply can't operate off of the curve. All you get to do, as the operator, is choose where on the curve to be. You can apply whatever voltage you want, and the curve will dictate what current flows. Or you can choose what current you want, and apply the voltage that gives you that current. The device that you need to do both of those things is a constant-current-constant-voltage power supply.

What you've been told ("the voltage needs to remain at the same level whereas changing the amps with move the spool") is probably just a simplification of the fact that the current-voltage curve in the region of interest has a very high slope - so only tiny changes in voltage are needed to produce large changes in current. Or, put another way, the desired change in current will only require a tiny voltage change. Or they were just wrong, and misunderstand it themselves.

Now try and recreate that chip using only discrete components so you can understand how it actually amplifies signals. You should be able to make a little push-pull amp with only two transistors, some supporting components, and maybe an impedance matching transformer for audio output.

Edit: http://www.circuitstoday.com/push-pull-amplifier

Edit: also, not even joking, maybe you can pick up one of these: https://www.amazon.com/Maxitronix-200-in-One-Electronic-Project-Lab/dp/B0002AHR04

I had that as a kid in the 90's and it really jumpstarted my understanding of discrete components. I learned the hard stuff first because of that kit, and only later in the 2000's picked up microcontrollers. At sixteen years old in '98, I built my own working guitar pedal, was so proud of myself because I learned the basics from that kit. It did distortion by overdriving with a preamp stage and also had a 8-ohm speaker output for portability. It sounded like utter trash, but it did what I wanted.

Elenco multimeter kit . You can buy one for about $30 on Amazon. Recommend the analog one for developing soldering skills.

Mixed reviews but it'll at least let you learn about components and soldering skills.

Relatively simple option: get a buck power supply and connect the fans to them.

Something like this for instance.

Note that it has a minimum voltage drop.

Get a brass shavings cleaner. I don't like the wet sponge method
https://www.amazon.com/Aoyue-Soldering-Cleaner-sponge-needed/dp/B005C789EU

I had a Radio Shack branded 200-in-One project kit when I was a kid.

Edit: This 500-in-One version has a breadboard also.

http://www.amazon.com/RioRand-LM2596-Converter-1-23V-30V-1Pcs-LM2596/dp/B008BHAOQO/ref=sr_1_13?ie=UTF8&qid=1459311307&sr=8-13&keywords=dc-dc+step+down

not this exact brand, but identical design.

If it is a prototype or a "one of a kind" use, i would go for a Buck converter module.

Aliexpress - Car Charger DC Converter Module 12V To 5V 3A 15W with Micro USB Cable

Amazon - RioRand LM2596 DC-DC Buck Converter Step Down Module Power Supply Output 1.23V-30V (1Pcs-LM2596)

These may work? Engineer PA-09 Micro Connector Crimpers https://www.amazon.com/dp/B002AVVO7K/ref=cm_sw_r_cp_awd_Xn04wbW5PE1TR

Never use abrasives on the soldering iron tip. First, use a wet sponge to wipe off the tip before soldering. If there's krud building up that doesn't come off with the sponge, wipe it on a cleaning wire. If the tip gets really bad, it can often be restored with a chemical tip tinner.

Like other posters have said, to make the tip last longer leave a blob of solder on the tip when you are done soldering, wipe it off before starting soldering. And turn the iron temperature down when not using (I turn it down to 450F when it's idle).

I too am fine with users who are active in the sub linking to their own on topic stuff. Going on the unique spelling of the username, I think it's this:

http://www.amazon.com/Battery-Management-Systems-Large-Lithium/dp/1608071049

Looks like it's for bigger systems than RC batteries.

/u/1davide I'll delete if you want to stay anonymous, but your username I suspect you aren't trying to :-)

I am building a proof-of-concept/prototype at the moment. Once I cobble it all together and confirm that it works, I will have to pay someone to design everything into a single PCB.

I was leaning towards this solution for the prototype:

12V 6A AC Adpater

LM2596 Buck Converter

Holy balls, for a buck? I wouldn't trust it...

What about some of these off of amazon? I just searched for LM2596.

This is not a recommendation, just some examples of what exists on the low end for bench supplies (off-the-shelf in the US):

KORAD KD3005D Precision Variable Adjustable 30V, 5A DC Linear Power Supply

That's a single output channel for $85.

I have something very similar to Triple Linear Variable DC Power Supply, Adjustable 30V/5A. There are many lookalikes. That's two adjustable channels, plus a fixed 5V (which I never use) for $180.

When working with a cheap supply, I:

• don't leave it on unattended or overnight
  
• always disconnect the load before turning the power switch on or off.