Homemade 18V Battery Stereo

Bear with me here, This is my first instructable and I already built this but I thought I'd give it a go.
First: Attempt at your own risk, don't hurt yourself and I am not responsible for any damages from anything that may occur.

Motivation: I just recently purchased a 18V cordless tool set and couldn't find a radio to run off the batteries (as some of the big brands make such radios), so i decided to make one.

Parts: (some are optional, all depends on what exactly you want it to do)
-Car Stereo (I had an old Pioneer laying around)
-Speakers (I got 5.5" Boss Marine speakers on Amazon, they shouldn't be bothered by a little water)
-Antenna (Pyramid 3800 from amazon, keep in mind how to mount it, I had to buy a longer screw for the thickness of the wood)
-Fuse Block (protect all those delicate components, ebay)
-12V Power Supply (I got a 5A light supply from ebay, just search for "12V 5A Power Supply" they are like $10)
-120V Relay (once again ebay, make sure it has 3 separate sets of contacts)
-Switches (1 toggle, and 1 push button)
-Wood for the box (I had some OSB with Mossy Oak print on it laying around)
-Digital Panel Mount Voltmeter (ebay for up to 20 Volts, to keep an eye on the battery)
-12V outlet
-18V drill battery charger
-Corner braces
-hinges
-window lock
-handle
-misc Screws
-Extension cord to use as a power cord and plug for the charger
-Metal to mount the switches in etc (I had the metal inserts from old Radio Shack project boxes)
-Aluminum tape (cover the edges of the box, mainly for aesthetic reasons)
(these parts are for the circuit to knock the 18V down to 12V)
-3x 100n ceramic Capacitors
-100uF Electrolytic Capacitor
-4.7uF Electrolytic Capacitor (I used a bigger one but this is the one the circuit called for)
-1N4007 Diode
-7812 Voltage Regulator IC
-2N3055 Power Transistor
-Heatsinks (one small one huge)

Step 1: 18V to 12V voltage regulator circuit

I found a schematic for increasing the current capabilities of the 7812 voltage regulator on http://powersupplycircuit.net/2n3055.html that worked out really nicely, however It might not be a bad idea to look up a way to add more power transistors for high current handling, one works but it does get toasty warm, even with the huge heatsink I put on it.

(I know I soldered the components on the wrong side of the board, no need to remind me, noob mistake. Still works fine)

-3x 100n ceramic Capacitors
-100uF Electrolytic Capacitor
-4.7uF Electrolytic Capacitor (I used a bigger one but this is the one the circuit called for)
-1N4007 Diode
-7812 Voltage Regulator IC
-2N3055 Power Transistor
-Heatsinks (one small on huge)

Comments

[richms]

There are some quite cheap switchmode 24-12v step downs available on ebay. The one I have tried works ok on down to about 16v and gives a 13.8v output for running car stuff in a 24v truck.

Anyway, they will have much better efficiancy than a linear regulater.

Also I dont know about putting line voltage on the same fuseblock that you have low voltage on. i would seperate it out and use a mains rated fuse holder, not a car style one.

[Grasshopper1221]

Yup for sure it is very cool. However that foil just don't do it any justice. steampunk the case and that would be kickass!

[tutdude98]

Nice man but it will be nicer without that foil