Evil Genius: Mechatronics. 1st project resistor

[lorenb]

Hi, I recently bought the evil genius: mechatronics book and it say you need a 1M ohms x 1/8 watt resistor (brown, black, red) I was planning on ordering this and other materials from alliedelec.com, but then i saw that the color code for the 1 megaohm resistor isn't brown,black, red. I looked up how to read color code and found that it should be brown,black,green for 1 megaohm. So he either messed up the color code or put the wrong resistance down and it should be 1k ohms. anybody know which one it is or if I'm missing something.

Thanks,
Loren

[want2learn]

Really, to figure this out without having seen the book (as I've never heard of it) you would need to post a schematic. You haven't told us what type of circuit you are referring to.

Although since the schematic is from a book it may not be ok to post it freely on the internet.

On the other hand, if the resistor isn't protecting any components that are expensive you could buy the 1K resistor and the 1M resistor and try them both . It's not really sound advice but hey, If nothing expensive will be damaged then why not.

[galannthegreat]

what project is it? I have done most of the projects in that book so maybe i can help you.

[lorenb]

its the 1st one with the race car

[galannthegreat]

Try out the 1M ohm resistor, it shouldn't hurt anything, because I can't seem to find the car I made.

[SmAsH]

id say get both and try the 1m first as too little power wont really harm much will it now?

[Razor Concepts]

Don't think in that mindset because if the resistor is part of a voltage divider circuit, the 1M could take so little power that a lot of power goes through the other way.

[SmAsH]

ok how about emailing/calling them and demanding to know the correct resistance!

[galannthegreat]

Hmmm.... of all things even I have not thought about, maybe google it.

[want2learn]

Don't think in that mindset because if the resistor is part of a voltage divider circuit, the 1M could take so little power that a lot of power goes through the other way.

Sorry, I did say though

It's not really sound advice

(Hangs head in shame)

[TrickyNekro]

Really..... post a schematic if you want help....
You need reference, and you are not going to copy the schematic out of the book...
Fortunately or not, in books it's not allowed to post a scanned version of the page...
But remaking the schematic in the eagle is another thing... You can literally do it without a problem...
You can say it's your schematic, cause you have design it, and if you got reference from a book you
may want to post it or not....
Copyrighting an electronics schematic is really not relevant.... Thousand same schematics may exist....
So... Make it on eagle and post it... easy....

I could just guess that it's 1K.... Usually, first projects refer to lighting and LED.... so... I guess that it's 1K...
I also guess that's it's an 1K resistor cause when he describes the colors he describes a 1K resistor...
Also see how close it's that M on the keyboard to the K..... So... Post a schematic.... I can't really smell my fingers...

[Soeren]

Hi,

its the 1st one with the race car

If you use 1 Mohm, it will take total darkness to shut off the motor (might not even be enough), so you should go with 1 kOhm.

[galannthegreat]

K, I've found the book and project that I did, just look at the wiring diagram (schematic if you call it that) they show what you need.

[Soeren]

Nah, the schematic shows 1MOhm which is way too high.

[vialick]

Have you been to the books/publisher's site and searched for the errata?

books often have mistakes, especially technical books. I know the series (for the evil genius) and it's aimed at the layman rather than the scientist, if you're still unsure, fire the publisher an email.

You pay good money for one of these books, you shouldn't have to troubleshoot their designs (unless they explicitly want you to)

[Newton C. Braga]

Hi, I recently bought the evil genius: mechatronics book and it say you need a 1M ohms x 1/8 watt resistor (brown, black, red) I was planning on ordering this and other materials from alliedelec.com, but then i saw that the color code for the 1 megaohm resistor isn't brown,black, red. I looked up how to read color code and found that it should be brown,black,green for 1 megaohm. So he either messed up the color code or put the wrong resistance down and it should be 1k ohms. anybody know which one it is or if I'm missing something.

Thanks,
Loren

Hi, I´m the author of the book Mechatronics for the Evil Genius; I´ve been using the 1 M (brown, black, green) resistor with my pupils since several years with success. The idea is start the motor when the sensor is iluminated and stop and when it is convered. But you can replace the resistor by a 1 Mohm potentiometer and adjust the light level to start the motor.

Thanks
Newton C. Braga