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I am new to electronics and I have a female USB PORT, a solar cell, a cell, a 2xAA holder and some wire. How do I connect it to each other so that the solar cell charges the batteries and then in turn give power to the USB port? The solar cell is a 6V 120mA. I just want to know. Thanks!

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What do you want the usb device to power? If you just want a usb charger, then forget the batteries and just use the solar cell. If you want the usb port to power a more complicated device, you should probably use a voltage regulator because neither the solar cell nor the batteries will give you the kind of steady voltage a computer can put out. – Feynman Apr 22 '12 at 15:09
"Female USB port" means little since cables have male ends and devices female. It's not clear if you are trying to charge the batteries from the USB thereby being a device, or provide power to the USB thereby acting like a host. Also, one cell and a 2x holder doesn't make much sense, and you didn't say what kind of cell. – Olin Lathrop Apr 22 '12 at 15:47
The usb hole should power for example a mobile phone charger or USB fans such small gadgets. How do I use a voltage regulator and how would it work? – Petar Apr 22 '12 at 16:09
Welcome to Electrical Engineering! I understand that you want to try this project, however, please understand that this is an engineering stack exchange, not some instructables forum. Please describe in clear detail what you're trying to do and what's not working! If you've got no idea where to start, then this is not the place for you - perhaps someone can help you in our Electrical Engineering Chat room. Once you encounter a real problem, feel free to bring it back here. Also, please respond to requests for clarification by editing the question. – Kevin Vermeer Apr 22 '12 at 23:47
@Petar - It's now been 24 hours since I requested that you update your question. Since then, you've done nothing to describe the task in clear detail and the question has accumulated additional downvotes. As it stands, it's not an appropriate question for the site, so I'm closing it. Please feel free to ping me back if you make any edits and want it to be considered for reopening. – Kevin Vermeer Apr 23 '12 at 19:56

closed as not a real question by Kevin Vermeer Apr 23 '12 at 19:56

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, see the FAQ.

1 Answer

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Buy a LM78O5 Voltage Regulator, connect the solar panel to input. Now, the output... The USB has 4 conductors. The outer ones are the power. Connect them to the output of the IC.

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4  
This is useless to the OP since he is starting from a single cell. A LM7805 needs around 7.5 V input to work. – Olin Lathrop Apr 23 '12 at 11:31
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That's 7805, not 78O5! Yes, I know you can pronounce it the same way, but this is a very common IC, and especially if you want to advise it you ought to know the type number. – Federico Russo Apr 23 '12 at 12:22
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You can also use the 79<insert zero here>5. – fuzzyhair2 Apr 23 '12 at 15:16

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