Noob - lost in the why
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Please be positive and constructive with your questions and comments.

Noob - lost in the why

by pgriffy on Sat Mar 31, 2012 6:32 pm

I've had my experimentation kit for a couple of weeks. I'm not having any issues getting the examples to work, and since my background is coding, i've even been able to make it do things differently. For example, I combined the LED circuit stuff I learned in examples 1 and 2 to add them to the motor spin in example 3 so the green led got brighter when motor sped up and the red led got dimmer when motor slowed down.

The part I don't get is why a certain type of resistor is chosen, or even why a resistor is used instead of a transistor. Is it just as simple as these tutorials cover the basic circuits that would ever be used and I just add that circuit when I need it (like I did when I added the lights to the motor exercise)? Or is there more basic info I need to know that the tutorials don't cover?

My ultimate goal (at least right now) is to build something that would monitor my hot tub and tweet when it needed more water, or chemicals, or the heater failed. I get that alot of this is possible, I just don't know where to start as far as knowing what sensors, resistors, etc I would need.

More than willing to learn on my own, I just don't have the right keywords for the Google, so my searches aren't helping at all.

I'd sincerely appreciate any tips on where to start with the more basic ideas of electronics so I can understand why the parts were chosen for a particular circuit. Then I would know what parts I need for the stuff I'm trying to do that doesn't have an example.

My adventure begins March 2012 with an Arduino Experimentation Kit...

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Re: Noob - lost in the why

by franklin97355 on Sat Mar 31, 2012 7:21 pm

I think the main idea of the starter pack is to give you the arduino and a few things you will need to try it out without you having to go somewhere to get the parts. Your hot tub project is a good start. get a temp sensor, figure out how you will be able to tell if the water is low and you could use a pressure sensor or a current sensor for the pump. An ethernet shield would give you access to twitter and email. Start slow, plan extensively and have fun. Nothing you do will be without some form of gain (even if you blow up an arduino along the way ;) )

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Re: Noob - lost in the why

by jasonwebb on Sat Mar 31, 2012 9:13 pm

I strongly agree with franklin - start slow, plan everything! Use the old adage 'measure twice, cut once approach'. You should at least the basics of what you want to do before you actually physically do anything.

Try not to get too hung up on the 'why' in the beginning. You should play with the Experimenters Kit to learn about what the different building blocks are (resistors, transistors, capacitors, etc) and how they can be connected. Follow the lessons in the booklet one by one, making sure to get each one working. Then maybe try to combine a couple lessons, or at something of your own to a lesson.

The real, unabridged answers to the 'why' questions in electronics are often complex and not to be taken lightly. They are the reason why people spend years in school studying to become electrical engineers! My best advice is to just keep tinkering, because the best way to learn something is by practicing. Once you've learned the fundamentals of electronics and you still keep wanting deeper answers, you should think about picking up some more detailed books designed for engineers that really detail all of the mathematics and physical properties of the electronics world.

Ultimately, if you want to make projects and play with technology, just keep tinkering and making small steps. Before too long, you'll start seeing connections and possibilities!
Jason Webb - grad student, creative technologist, OSHW engineer
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Re: Noob - lost in the why

by adafruit_support_bill on Sun Apr 01, 2012 6:21 am

In addition to the lessons in the experimenter kit, you should work through some of the Adafruit tutorials. The Arduino tutorials cover much of the same basic material as the experimenter kit, but there are many others that go into depth on various sensors, displays, tools and techniques.

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Re: Noob - lost in the why

by zulucat on Mon Apr 02, 2012 12:55 pm

Pgriffy wrote:... The part I don't get is why a certain type of resistor is chosen, or even why a resistor is used instead of a transistor ...

It sounds like a book on basic electronics would help you out. As it turns out, Adafruit carries one:


I'm not familiar with this book but I assume that if Adafruit carries it that it has to be good.

I found a Table of Contents on Amazon that you may want to look at:


Good luck with your project!
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Re: Noob - lost in the why

by splonk on Mon Jun 18, 2012 9:45 pm

Yeah, I wondered why on the resisters with the LED, too. A resister can be used to limit the current through a circuit. Exceeding the maximum current on an LED can burn it out. Current on the I/O pins in 40mA (from http://arduino.cc/en/Main/ArduinoBoardUno) and the LEDs probably have a max lower than this. Don't know their spec. This might help you: http://www.kpsec.freeuk.com/components/led.htm
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Re: Noob - lost in the why

by bhuebner on Thu Oct 25, 2012 11:00 am

I was a newbie not too long ago and found myself wanting to build a hot tub monitor. I was wondering if you got started on your project and wanted to collaborate and share? I would like feedback on my Arduino hot tub monitor.

The project is posted here: http://openspamonitor.blogspot.com/

I started very slow, getting one sensor to work, adding an Ethernet shield, finding reliable code examples and adding and testing other sensors. It has been a great process, and I have learned so much. I had no prior experience with electronics and programming. Thats why I am sharing my design, as others have done, in hopes the people like you can learn from it and improve it. I would like to build a community like the open energy monitor, and I hope that you have time to participate in this project. It is not all that complex, but I am prototyping an RF version now and designing a PCB for the project.

Please get in touch with me and let me know what you think. I am interested in how your build is going, if you would like to share.

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Re: Noob - lost in the why

by gabriellem on Sat Jan 05, 2013 12:29 pm

Depending on the depth you want to go into, I have found these following college texts helpful:

College Physics Volume 2
University Physics Vol 2

The latter is aimed at engineers, the former is more general.

I am not in an engineering field, but I did take engineering physics and general physics a long time (20 Yrs) ago - so I'm basically a beginner again - but I am finding these books accessible.

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Please be positive and constructive with your questions and comments.