Recent content by ShadowPho1

More complicated method: microproccesor controlling a mosfet with the batteries.

This is a great thing you can do on spice :)

100 Hz is kinda low. Those do seem kind of expensive too. I wrote a small paper on making an H-bridge/CA module, if you want email me and I'll send it to ya. Now, the motors seems pretty small current. That means you have no need for hbridges that can handle 30 amps. Also, if you want it to...

Current is like the amount of water that flows. Generally power supplies can only give you a certain amount of current. If you go over they start heating up too much and go up into flames.

Then something is horribly wrong with the chip, power supply or the breadboard. :) Do you have a different 555 chip you can use? How far do you live from Chicago? (I can test one and send you one if needed lol)

Does it heat up if you only connect + and ground?

Rule of thumb - if the part gets too hot for comfort than it either needs a heatsink or you are doing something wrong (like reverse the polarity). For many chips if your reverse the polarity it will act as a short and will heat up very quickly. Does your voltmeter have a current measuring...

Energy in a cap = 1/2 c v^2 (had to look it up lol.) .5 * 6.8* 10^-10 * (20000)^2 = 0.136 joules Possibly lethal, but most likely a bad shock.

50 amps... holy moly. Would a bridge rectifier work? You can try a custom made charge pump to just quadruple the voltage.

I don't know the right answer... But maybe the circuit breaker for your house is rated at 30 amps while the one at the facility rated for... more than 30 amps? So the moment you go into 31 amps your house shuts down but you can theoratically get more than that?

Pull down resistor on TRIGGER_555 edit: currently you have a pull up on trigger_555, thus during power up it will turn HIGH first.

Thank you everyone for your help with this! The DAC worked flawlessly, the power amp works perfectly, the 0.25 watt speaker works perfectly, the microproccesor works perfectly. But I couldn't read anything from the SD card. Nothing at all. I thought I could do it, but I ran out of the time at...

Now, the hardest part in your requirement is the size. This'd be easy if it was two inches by two inches... as it stands now you'd need something surface mount. Now, let's think of how to store the data. 3 times open close = 6 changes a day. This means we'd need to store 6 dates per day. You...

Ah... gotcha... Hmm, she actually WAS pretty impressed with how me/parents painted the room. I love how this thread also generates girl advice ^^, MSP430F2012. It has an onboard ADC which I am not using, it has SPI which I am using heavily and it has no DAC. It's easy to program...

Very simple, the current is determined by the effective resistance of the element. The current through an element is based on resistance/voltage, and then just use ohm's law (V/R=I) The easiest case is resistance. The two ways to increase current through a resistor is to either up the voltage...