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[on:]

I'm new to adruino and the forums.  Looking forward to many exchanges in the future.  I'm starting simple...building ARDX samples and trying to learn from them. I got to the spinning motor exercise and for whatever reason can't get it to work properly.  This is the exercise: http://www.oomlout.com/oom.php/products/ardx/circ-03

Everything I've read is for problems getting it to spin, mine is the opposite... it won't stop spinning.  I built it exactly according to the layout: http://ardx.org/src/circ/CIRC03-sheet-OOML.pdf and and even copy/pasted the code after second guessing myself a few times.  But still I have zero control on motor.  In fact, even removing PIN9 entirely has no effect; it continues to spin.  The obvious is that the wiring is wrong but I don't know enough yet to second guess the layout.  Plus I haven't found a single post anywhere of this same  issue.  Assuming the wiring is right, my only last suspicion is a bad transistor but I'm no expert and after hours of reading I'm not any smarter on the subject or closer to solving this.  Please help.  

[Reply #1 on:]

Hi MadMike

In fact, even removing PIN9 entirely has no effect; it continues to spin.

Try grounding the lead to see what it does.

But my money is on the transistor.  Double check which side of the transistor you connected it to. You may be grounding the motor and bypassing the Q altogether.

Pat.

[Reply #2 on:]

Hi MadMike

In fact, even removing PIN9 entirely has no effect; it continues to spin.

Try grounding the lead to see what it does.

But my money is on the transistor.  Double check which side of the transistor you connected it to. You may be grounding the motor and bypassing the Q altogether.

Pat.

your probably right,turn the transistor around see what happens

[Reply #3 on:]

If you wired the motor to the wrong side, the motor should still spin if you pull the transistor off the board.  Try that...

[Reply #4 on:]

Whether I turn the transistor around or pull it out entirely, the motor does stop spinning.  It's not that I have control though, it's just unresponsive.  I also tried wiring the motor to the other side during each of these tests but there was no difference.

With the ARDX kit, I only got 1 transistor so it's tough to test/isolate it as the problem.  I'll make a special trip to get some new supplies today.  Only a foot of snow on the ground, this should be fun (yes, I am that obsessed to figuring this out).

Patduino, I'm not sure what you mean by ground the lead.  Do you mean taking the +5v lead and putting it directly to GND to complete the circuit? 

...and thank you for the suggestions!

[Reply #5 on:]

Could you post a picture or your schematic? What type of transistor are you using, PNP, or NPN?

[Reply #6 on:]

Could you post a picture or your schematic? What type of transistor are you using, PNP, or NPN?

The schematic is http://ardx.org/src/circ/CIRC03-sheet-OOML.pdf.  Mine is exact - sorry can't post photo right now, but trust me, I even pinned the schematic to the breadboard just to be absolutely sure I wasn't making a mistake.   According to the listed parts, the transistor is an NPN and these are the specs I found: http://www.futureelectronics.com/en/Technologies/Product.aspx?ProductID=P2N2222AGONSEMICONDUCTOR9557430&IM=0 
The part number was not on the transistor which is also one of the reasons I suspect it is either faulty or just plain wrong.  This is the part# I plan on buying (I can't be sure it's what I was sent).

[Reply #7 on:]

Is this your setup?

wow... I didn't think it would be that big, sorry.

[Reply #8 on:]

Do you mean taking the +5v lead and putting it directly to GND to complete the circuit? 

Dear god don't do that.

I think he meant take the lead that is connected to the Arduino digital pin and plug it directly into ground. That should "turn off" the transistor, preventing current from passing through it (and thus, the motor).

[Reply #9 on:]

Patduino, I'm not sure what you mean by ground the lead.  Do you mean taking the +5v lead and putting it directly to GND to complete the circuit?  

Sorry if I was unclear, ground the transistor base.  Arrch is right - that'll disable the transistor to help narrow down the problem space.  

Don't ground your +5v!  Unless that foot of snow knocked out your power and you are looking to heat your place... For a few milliseconds !

[Reply #10 on:]

Problem solved!  It was the transistor.  I can't tell if it was faulty or was the wrong part (as I said, I couldn't read the part#).  Thank you everyone for helping troubleshoot... so glad this forum exists.  This will be my second home for the next little while and so I hope to pay it back sometime.
Cheers!