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Am I likely to find a source of 12v inside a CD boombox? Answered

I'm planning on building my own kitchen under-cabinet stereo using parts from an old boombox and a CD-ROM drive.  I've been looking at 'ibles like this and this for inspiration.  I know that the CD-ROM drive will require both 5v and 12v input, and I don't expect to have much trouble finding 5v (or something higher I can drop down with a 7805).  What I'm concerned about, though, is finding 12v.

Eventually I'll be poking around in there with a multimeter, but I was wondering if anyone can tell me if it's likely that the existing CD player in the boombox would have run on 12v, or something lower.


.  Multiply the number of batteries by 1.5 and that will tell you the maximum voltage inside the box. Ie, if you have 8 or more cells, you're good to go. When poking around with your multimeter, the connections at the battery pack will give the greatest voltage. If you are using rechargeables, some of them only put out ~1.2V, so you may need to change the multiplier above.
.  If you are going to be using a wall-wart, just get one in the 15V range and use the 78xx's to step down to what you need.

My plan is to continue to use wall current, utilizing whatever power supply is in the device.

This will be my first electronics project, so I'm a bit apprehensive.  Thanks for the advice!

How many batteries does the boombox take? Most are running on something closer to 6-9V than 12V, and have no reason to run a DC-to-DC converter to push it higher.

Good question.  I don't have it with me, and I've rarely put batteries in it anyway, as I run it off of wall current all the time.  If it has 8 batteries, that would make it 12v, obviously.  :-)

Thank you!