Build The $5 Microphone Preamp

Step 4 Power Supply

The original Mic pre-amp used all batteries for both the chip power and for the phantom power. I figured that if I could get the power clean and stable enough from a wall jack that is what I will do.
The first thing is to get clean AC power from the wall. What I use is the Monster HT800, which is just a line filter and surge protection. From there I use an old laptop power supply to give me a DC current. The last step since there is still some rippling of the DC current I built a voltage regulator from the LM317. This is an adjustable voltage regulator which allows me to get the exact voltage I need.
There are no pictures for this step as I will be writing another instructable on how to build the voltage regulator.

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UPDATE

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I decided to change the power supply a little bit but for the most part, it's the same. I am just using a laptop charger which just connects to the TI's rail spliter(TLE2426). i'm thinking in the future of actually using the LM317 but for now i just have the rail spilter. the schematic for the TLE2426 is found on http://tangentsoft.net/elec/vgrounds.html
it's about half way down the page.

Comments

[jeandeau]

Have you posted the power supply for the preamp? I searched the instructables site and didn't find it. thanks