Power Line C-L-C Filter For Car Audio

Inspired by the great looking of Pioneer Carrozeria RD-7X, I would like to build this power line filter by myself. This power line is usually for clean up the ripple cause from the alternator of the car. Main purpose for this unit is for cleaner power line to the car's head unit. Since this is very simple project, I could dig all the components from my bin and the cost for building this is almost nothing.

If you wondering what is RD-7X is like, then I post the photo taken from the web. This is an official picture of this product.

The components inside is a coil and capacitor. Additional is fuse and terminal. This configuration is L-C filter. The what I am doing in my project is adding another C in front of the L, so the final schematic would be C-LC filter.
As you can see I am using four 6800uF 35 volt from Elna RJ4, then a coil taken from old car amplifier and a universal board. The layout would be like this:

Always remember to clean the coil enamel before joining otherwise it will not conduct.

If you wish for the schematic, then it would be like this:
(the two 100nF is actually hidden underneath the coil transformer)

The schematic is very straight forward. The input voltage is taken directly from the +12 volt battery to filter. The output from this filter would be connect to the input +12v of the head unit. With this wiring method, you can get full potential power to the head unit rather than wiring it to the OEM cable. 

Disclaimer: Any statement and photos in this article are not allowed to copy or publish without written permission from the writer. Any injury or loss from following tips in this article is not under writer responsibility.