## Step 5: AC to DC?

AC current stands for alternating current witch means that the power changes from positave to negitave and then back to positave and the other wire being ground.

DC stands for direct current and means that one wire is always positave and the other is always negitaive or grond

AC is not as usefull as DC but things like transfourmers cannot run off DC and it is easyer to convert AC to DC so mains power (the power that is supplyed from wall plugs) supplys AC.

AC wich is a problem for us becausThe transfourmer supplys e batterys olny supply DC, and DC it is harder to convert into AC.
Luckley the circuit that was in my speeker had four diodes aranged as a bridge rectifyer. A bridge rectifyers purpose is to convert AC to DC witch is what our batterys supply. This means that what looks like our board draws AC the board its self  actually converts it into DC before it reaches anything so we can connect our batterys directley to the input.
<p>can i connect a 6v lead acid battery? but it is 4.5ah.</p>
<p>Could someone please assist me, on a cell phone (hopefully standard) how much current is sent to the speakers?? Grandson question, does it need more power for a higher pitch or less. I feel like a fool as he is 7?? Lol</p>
<p>The amount of current you send to the speaker determines the loudness of that speaker. Different speakers have different current ratings. It depends on what speaker you have. I'm not sure if there is a 'standerd' output for cellphone speakers. But see if there is an ohm rating and a watt rating on the back of the speaker.</p><p>What determines the pitch of the speaker is not the current it is drawing. It's the frequency of the signal sent to it. To run a speaker a wave generator outputs signals to it, the frequency (or pitch) depends on the frequency of the input. </p><p>Probably youtube can explain better than me!</p><p>https://www.youtube.com/watch?v=DMxn3CPLe-A</p>
From what I see, you left the bridge rectifier diodes in the circuit. They will likely cause the voltage from the batteries to drop about a volt, or about 0.5 volt for each of two diodes through which the current will flow. But, they also insure the polarity from the batteries cannot be applied in reverse, even though the terminals on a 9 volt battery pretty well prohibit that, anyway. <br> <br>I know the batteries will be depleted one day, anyway. I would probably want an easier way to open the speakers to change the batteries. <br> <br>It is always fun to make electronic devices more useful for your particular needs and purposes.
I was actually looking at replacing the batterys with some 9.6V ni-mh batterys. An then adding a chardging plug.
yea.. <br>you can use super cheap electricity from the wall, but that is boring. <br> <br>spend all your money on 9V batteries.. <br> <br>
I made this for calling ducks and geese. Its not quite loud enough but stilll works well. Of corurse there is no wall plugs where you are hunting.
wtf why so many instructables about the same concept <br>ITS JUST CUTTING 2 WIRES AND CONNECTING THEM TO A FREAKING 9V CLIP JUST MAKE SOMETHING ORIGINAL!!!!!!!
I acutally made this for a compitition but missed the deadline by seconds. No other compititions came out so I decided to relice it.
thanks for pointing out the use of diode as bridge rectifier. i can't figure out at first how some people can use 9V DC to replace a 9V AC transformer in their basic computer speakers.