I am almost there! Please help!!

[inkedallusion]

I have been searching for the cheapest, easiest design to build a power supply. I am pretty new to this, but I found a design using an l200 voltage regulator that would work great. I iam not sure what sort of power output I need though. The load will be two eight or ten wrap coils with 24 gauge wire, and a 1 uF cap in paralell with them. How do I know what the load will not to run correctly? I am thinking I need about 2A, 15 volts or so. I don't think I really need adjustable voltage, just the current adjustment.
Here is the link I am looking at for the idea- **broken link removed**

One other thing. I have seen a power supply like what I am trying to build and all it was was an unregulated supply using two 1000 uF caps after the bridge rectifier with a filter choke in paralell. This went to a power rheostat to limit the current. I want to improve the design, PLEASE HELP!!!!! I want to thank all the people who have been answering my questions, I have learned a lot. Thank you!

 

[elegeek]

hi

hi
jus out of curiosity ,y do u need two amps at the outout,r u trying to drive a solenoid as a load(coils),could u elaborate on the load u r to encounter in the ckt.
u have mentioned at the start u r looking for a simple design .y do u need two amps.is it a must?????.
don't know whether u r a beginner or have done a bit in electronics.
a simple 7812 or l 320,lm340 should be able to do the trick.rectified input should be 17 volts to the lm320.if u can suffice with 12 volts 15 volts should suffice.i believe if u require 2 amps u must have a heat sink for any regulator u use.i am not an expert in this field ,but talking from exp:
hopefully this is of some use to u
bye

 

[bogdanfirst]

well, he cant use a 7812 because it only support 1.5A max, even with the biggest heatsink....maybe use 2? and ifu want 15 volts use a 7815 or 2 of them if u need more thann 1.5 amps....
and another thing for the 78xx regulators the imput voltage must ba at least 3 v highter than the output voltage

 

[herbymcduff]

I would have to say also that if you are to use regulators, place a diode across the in and out. The cathode to in, and anode to out. Then I would place a small 1mic to 10mic cap right at the in and out. Place as close as possible. The caps keep the regulator from oscillating. The diode is needed for reliability. Your output voltage cannot exceed your input, or you will ruin it. I agree with bogdanfirst, your in voltage needs to be 3v or higher than your out. On the current thought. I wouldn't go as high as 1.5 even. Even though you can, it still isn't reconmended. But what do I know? :mrgreen: