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1  Products / The Arduino Starter Kit / Re: Problem with unstable Tilt Sensor [Too short pins] on: June 03, 2013, 11:41:48 am
As shown in the diagram, the tilt sensor always pops out, but then I also have trouble keeping the potentiometer on the board (due to the rectangular pins).  To get the system to work, I have to hold a finger on each of those components, forcing them into the board.

If i move the tilt sensor, it stays on more often, but will still pop off on occasion (every 5 to 10 times i tilt the board). Moving the potentiomenter won't change how bad it fits into the board, so i still have to keep my finger on it (or replace it with a fixed resistor).
2  Products / The Arduino Starter Kit / Re: Project 09 (Motorized Pinwheel) problem - motor spins forever on: May 31, 2013, 07:51:25 am
I don't have the book or schematic in front of me, but from the pictures it looks like you're wiring the motor directly to the power.  You have the hot/red wire directly connected to the right-side power strip (assuming that the 9v supply is attached at the top) and you have the black  connecting through the diode to ground.  Where's the "switch" to turn that off?

EDIT (6/1/13)
Am now at home, looking at the diagram it seems that the diode goes to the positive bus, not the negative bus as your picture shows...
3  Products / The Arduino Starter Kit / Re: Problem with unstable Tilt Sensor [Too short pins] on: May 31, 2013, 07:33:06 am
You are right in that the sensor pins are very short.  And pushing the back won't completely solve that - I have the same project currently assembled and the sensor still pops off from time to time.  But it's not as bad as it was when I had it over the unsupported section of the breadboard.
4  Products / The Arduino Starter Kit / Re: Problem with unstable Tilt Sensor [Too short pins] on: May 30, 2013, 02:17:09 pm
Assuming you are using the starter kit, and have the breadboard on the wooden panel, see this thread:

Unfortunately, the picture is no longer available that shows the problem. The solution is to either move the tilt sensor to another location that is properly supported by the wood or to push on the back of the breadboard to get the contacts back into the proper location.  The second solution is, however, only temporary as the board will soon have the same problem. 

By the way, I have similar problems with the potentiometers flying off. 

Hope that helped.

5  Products / The Arduino Starter Kit / Re: If your components don't sit well on the breadboard, try this! on: May 03, 2013, 04:32:51 pm
Thanks for the suggestion!  That made a huge difference!
6  Products / The Arduino Starter Kit / Re: Project 04 on: April 29, 2013, 07:31:28 am
Not sure what project you're doing, not sure what LED you're using.  However, most RGB LEDs have different forward voltage values, so you can't use the same size resistors on all three channels.  And if you are using a single resistor on the cathode, you're doing it wrong.

Here's the spec sheet for the RGB LED:

Forward voltages are 1.95/3.3/3.3 respectively. 

As for the number and size of the resistors, going from memory (don't have the book in front of me at the moment) I think the
resistor strengths are all the same.  Maybe someone that has the book handy can check.
7  Products / The Arduino Starter Kit / Arduino Projects Book suggestion on: April 28, 2013, 09:41:56 am
Not sure if this is the right place to post this, but I'd love for the project book that comes with the starter kit to be spiral bound.  I find holding the book open while trying to wire the board to be impossible.  On the plus side, I am really glad the book has the 'bookmark-flaps'. 

8  Products / The Arduino Starter Kit / Re: Project 04 on: April 28, 2013, 09:33:56 am
I have the same, I suspect it's either a weak 'green' component in the LED or our eyes are just much more responsive to blue and red, so they drown out the green. In the end I ended up dividing red and blue by 10 and green by 3 to make the different colours visible

Sorry about my noob question but, how do you know for how much you have to "divide" the colors, or you just tryed different values till you get the led glow white?

Open the serial monitor and look at the values.  In my case, the r-g-b values are 131, 105 & 86, which should imply a reddish-green color, but it's more purple (reddish-blue).  Getting white is very difficult, as the green element just doesn't transmit well (due either to our lack of sensitivity to green or to a weak green LED element). 

I manually set the values to see what different ratios gave and the only way I could get a good green led was to set the r-g-b to 3-255-3.  Even setting the red and blue to 5 made the light noticeably non-green. 

To get a white led (ok, mostly white when looking from the side), I manually set the values to 20-255-20.  Once the red and blue values hit 50, the color was noticeably blue-purple.
9  Products / The Arduino Starter Kit / Re: Project 11 first returned random value not random. Why? on: April 24, 2013, 07:57:41 pm
FWIW, I have the same problem with the tilt switch.  Not sure if the pins were pushed too far in or if they're just not long enough, but they don't like to stay engaged in the board.  They make contact with the metal in the breadboard, but it feels like it's spring loaded.  If I don't keep pressure on the sensor, the thing just pops out. 

10  Products / The Arduino Starter Kit / Re: COMPLAINT: Starter kit components not fitting on: April 22, 2013, 08:40:21 am
I just completed project #5 and had many of the same problems you've identified.  While I've had some electronics training (undergrad electrical course more than two decades ago), I am by no means an expert. 

The most frustrating part so far is the components not staying in the board (especially the buttons and the potentiometer).  In order to make the project work properly, I had to keep my finger pressed on the potentiometer, pushing it down into the board and ensuring proper contact was made.  I haven't gone down the route of soldering on leads as I would really like it if the pieces sat on the board (like shown in the diagrams). 

I wonder if crimping the rectangular pins into more of a square cross-section would help them fit?  But you'd have to be very careful you don't break them instead. 
11  Using Arduino / General Electronics / Re: Proposal: Newbie Guide for Electronics on: April 15, 2013, 08:09:22 am
One of the problems with a "beginner's guide" is defining what you mean by "beginner"? 

If all you're looking for is a general guide on how to connect components, then things like the above-mentioned cards do a great job in holding one's hand.  In this case, a "beginner" has a significant understanding of electronics and only needs practical information of how to put things together.

If, however, the beginner doesn't understand the "why", then the "how" makes little difference in getting something to work.  Again, (and strictly as an example) going from the OP, if we want this guide to discuss "why" we need a decoupling capacitor, then that's a much more theoretical exercise, and trying to explain that will involve a lot of editing so that the simplifications made in order to make it accessible don't create a misrepresentation of how the device works.  In some ways, Wikipedia is a great source for this type of "why" information at the component level.  For instance, the wiki page of transistors does a good job of explaining what it does and why they're so useful. 

With all of this said, in my 25+ years of engineering I've found very few people who can make the "why" accessible to the novices. 
12  Using Arduino / General Electronics / Re: Proposal: Newbie Guide for Electronics on: April 14, 2013, 12:08:01 pm
I propose we create a newbie rule guide for this forum that we can make sticky and point beginners to that might help cover 90% of the problems on this site.  A sort of top 20 newbie rules thing.

Here is few examples of what I have in mind.

Rule #1: Always use decoupling capacitors.  At least one decoupling capacitor should be used for each power pin on each IC and be placed as close to the power and ground pins of the IC as possible.  If you have not done this yet, do not post a question on this site.


Whud'yall thank, huh?

And herein lies the problem:  To do something like this justice (if you're truly looking to inform a newbie), you have to make sure you refrain from using jargon, or at least when you use jargon you point to where it's defined.

For instance, assume I'm a newbie (not far from the truth) and have no technical knowledge whatsoever (not quite true... but close enough).  In your #1, a newbie would read that and immediately wonder what is a "decoupling capacitor" and how is it different from the brownish disk capacitors and the bluish cylindrical capacitors that I got in my really cool starter set? And if i have to put one of these new capacitors in the power pins, why didn't i get them in the really cool starter set?

Just to let you know more about me... I'm an engineer, but not electrical.  I "got through" my electronics classes by converting everything to pipe flow and going from there.  I'm also a firm believer that electronics run on smoke and that when you let the smoke out of the pipes/wires, you will have to hire someone to fix the leak and put the smoke back in... :-)

And to bring it all back around, I have no idea what a "decoupling capacitor" is...

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