Converting 50v into 12v

You should be able to build a pretty simple supply, based on your application. I'm not sure how much power your trying to get, so the resistors will vary, however you should be able to get a steady 12 V output with a reverse biased 12V Zener and 2 1K resistors, that would work as long as your load resistance is greater than the 1K line resistance. Another option is LM317 Transistor, a 8.6K Ohm Resistor and a 1 K Resistor and 2 1uF Capacitors. As long as you don't increase the input voltage over 50 or decrease the ouput under 12, I'd go with the LM317 and a good heat sink.

thats helpful  thanx .

for sever months a tried to learn to get the correct equipments and how to connect it togther .

then i found those

http://www.newark.com/jsp/search/productdetail.jsp?sku=41K4634

http://www.newark.com/jsp/search/productdetail.jsp?sku=90R8782

http://www.newark.com/jsp/search/productdetail.jsp?sku=59K8386

http://www.newark.com/jsp/search/productdetail.jsp?sku=58K4984

but i dont think those are the right tools and i could not know how to connect them .

the idea is that my phone cable gives 45-50v , and i wanna charge of of my devices that needs 12v to charge .

Right, those won't do much for you. The LM317 is a variable regulator and will output different voltage based on the ratio of the resistors. You'll need higher power resistors if you're wanting to pull higher current. The voltage regulator will have a 15W maximum ouput, so at 12 Volts, you'll be able to pull a little more than 1A. Not sure what kind of devices you want to charge or what their current draw is going to be.

This one should do fine.

http://www.newark.com/fairchild-semiconductor/lm317ahvt/ic-adj-linear-reg-1-2v-to-57v-to/dp/82C8147?in_merch=Popular%20Power%20Management%20Products

thats my plane .. but could not know to build it

Here is what the layout should look like, those are arbitrary resistor values in there currently. Set R1=1K and R2=8.6K Ohm. Keep the Capacitor values the same. The pins will be lined out as such:

This will work for all my plane parts ?

Yes, will give you a regulated 12V and at least 1.5A of current. I would also throw some sort of current regulation on each of the lines depending on what you're plugging in, just to protect against over current. That will work fine though.

im just i beginner, i will try to design the plane then i will show it to you