Let's Make Robots!

IR LEDs and transistors voltage

Anyone knows the voltage and currents for these devices? There seems to be ABSOLUTELY no information. I bought them from yourduino.com because I told myself I could figure it out but I now highly doubt this. *facepalm*



Can a 3,4V solar panel charge a 3,6V NiMH battery pack?

Can a 3,4V (open circuit voltage) solar panel charge a 3,6V NiMH battery pack?

Arduino reseting/not following code.

When I connect the FTDI cable to Arduino, the whole robot starts working and executes a basic object-avoidance code. When I take it off and connect the power source, the robot starts to execute bits of code in a random sequence. The Arduino isn't resetting, but the red light is varying in intensity. Sometimes it almost goes out. I'm using an Arduino Pro Mini. Because the green light doesn't blink, I suppose the 2AA batteries aren't good enough to dish out 2A or more (I use 2 GM9 motors and I geard Arduino can use up to 1A).

Making a fire sensor (question)

With a bit of circuitry can this IR phototransistor replace the following sensor? 

IR phototransistor:http://arduino-direct.com/sunshop/index.php?l=product_detail&p=209


I plan to interface it with an Arduino

How to use small radio speakers- with Arduino

Small SpeakerHow do we use these? I salvaged 3 of these but I have no idea how to use them. Google searches were irrelevant and the closest I came to finding an answer was the Arduino Tone example. Can you please indicate me a good tutorial on that subject if you have one in mind? 

Thanks a lot

Can this breadboard handle 2A?

I plan to use 5V at 2A (10W) with this breadboard. It`s pretty small and cheap but I`m afraid it might not be able to handle 10W. 


Where do you buy your electronic components?

In the past, I didn't need electronic components because I thought it was too complicated. Now that I've learned more, I want to buy some ecomponents to start building/hacking circuits. Where should I buy electronic components? Where do you buy yours? 

Solar Battery Charging (2xAA)

I have searched the Internet for ways to charge batteries via solar energy. I know that I can charge a NiMH battery forever as long as the current doesn`t go over a tenth of the battery`s capacity (which is, in my case, 245mAh). Because I will be using two NiMH batteries connected in series I will use the following Photovoltaic module:  http://www.robotshop.com/ca/SP3-37-powerfilm-solar-cell.html. I guess that I`ll connect 2 of these in parallel which should give me 44mA.

Question regarding voltage regulator Amp output

http://www.robotshop.com/ca/dimension-engineering-de-swadj.html Does this voltage regulator output strictly a 1.5A current or will it output as much as the load demands (I will have 8 or 9 DAGU microservos at 6V and I honestly don`t know how many Amps that takes but I would guess somewhere around 1.5?). I`m just getting really confused from reading all these data sheets... they`re driving me crazy! 

How did you cope with the Arduino Mini 5V

The Arduino Mini and a bunch of other electronics require a 5V power source. The only way I can achieve that using standart batteries (AA, AAA) would be to use a power regulator (preferrably a low-dropout power regulator which I can't find on robotshop). So how do you suggest I get my 5V? It doesn't need to work with standart batteries - as long as the solution is cheap. What other online store would be good for a low-dropout voltage regulator? 

P.S.: This website is awesome!