DC Voltage.. Where's my electrical minded people?

[SuBrat84]

Okay.. So. I have this AC to DC adapter that the cable company gave me as part of a set-up in an attempt to "Boost" my signal power or something because they don't know why my highspeed connection is a POS. Well I took the thing off and it didn't make any difference. If anything it works better without the thing. Anyway. It plugs into your standard 120 plug in your home. Then a standard Coaxial cable plugs into it, then the other end plugs into this little box that is the "booster" .. Well After pulling it through my block wall the box end popped off. (Yes, I unscrewed it off the box. Just the little "Nut" popped off.) I was looking at it and the "transformer" said Input: 120 Output: 12v DC .. DC? Like Cars.... So I put my multimeter on it and it is putting out a very steady 20.3VDC. What I'm getting at here is.. would it be okay to splice the coaxial cable onto a set of jumper cables and use it as a battery charger? Would it be dangerous without some kind of regulator? Can a car battery get "too full" or will it just stop taking a charge once it's "full" ? Would I be able to use this theory to install a car stereo in my home? Thoughts? Ideas? Complaints? Rants? Let's hear what you have for me!

[stumpy]

Yes DC like cars.

Altenators put out like in the 13-14 volt neighbor hood if I remember correctly.

Yes, a battery can over charge and cause problems (Explosion is the worst). Regulator or timer would be advised.

20 volts seems a bit high to me if you want to run directly off of it with a 12 volt divice.

I'm not an automotive electrical expert by any means so second opinions please! And corrections welcome. Stumpy

[fastenova]

Sounds risky to me. I agree that 20V is very high for a car battery. You want amperage, not voltage. I'm guessing you're probably not going to be pushing many amps with that thing, and it would be the equivalent of a trickle charger. Those are CHEAP to buy, say $25 or less, and they've got the regulating circuit built in. Exploding batteries are bad.

 

As far as running a stereo, get an old computer power supply and short the soft power line, mount a switch on the case, and you've got all the 12V you need, if you get a decent one they're ~300-350 watts. Or you can look around for a benchtop 12V power supply, they're usually pretty cheap. I think most 12V devices will take 10-14V and be able to adjust for it but much more/less than that and you start having problems.

 

Just my 2 cents.

[SuBrat84]

Tested it: 0.150 amps if it matters.

[fastenova]

Wow, high power. That's all of 3.045 watts. Definitely couldn't do much of anything with that. Most trickle chargers are 2 amp or 6 amp.

 

You could run a car stereo with no digital display and maybe one little tiny speaker!

 

I think that signal booster they gave you may amplify certain frequencies, whatever freq. cable comes in on. Does the box have any model number on it or anything? As such, I wouldn't suggest using it just as an AC-DC converter, as it would probably put out some funky signal. But I don't know much about signal amps, really.

 

EDIT: If you end up going with a computer power supply, take all of the 12V lines (Red I believe, Yellow should be 5V and black is obviously ground.) and solder/crimp them together on one end, then use an 8ga or so cableout of them to run to an amp, if you want to run an amp directly off it. If you're going right into a deck, you can use smaller (14ga or 16ga) wire as the amp's internal to the deck. If you want a power supply, let me know, I'm getting rid of a bunch of equipment at work and you could have one for the cost of shipping. I have converted a few of these to bench power supplies to test components (fans and the like).

[johnceggleston]

there are lots of power supplis for 12v dc. also 12vac, or 16vac, or 24vdc. it all depends on what you're trying to do. how much juice does a car stereo pull.

 

almost all home alarm systems run on 12v dc. so you could tie in there if you have one. i dreamed of hooking up a car cigarette lighter to mine. but what would i use it for that i couldn't do with 120v ac??

 

Wow, high power. That's all of 3.045 watts. Definitely couldn't do much of anything with that. Most trickle chargers are 2 amp or 6 amp.

 

You could run a car stereo with no digital display and maybe one little tiny speaker!

 

I think that signal booster they gave you may amplify certain frequencies, whatever freq. cable comes in on. Does the box have any model number on it or anything? As such, I wouldn't suggest using it just as an AC-DC converter, as it would probably put out some funky signal. But I don't know much about signal amps, really.

 

EDIT: If you end up going with a computer power supply, take all of the 12V lines (Red I believe, Yellow should be 5V and black is obviously ground.) and solder/crimp them together on one end, then use an 8ga or so cableout of them to run to an amp, if you want to run an amp directly off it. If you're going right into a deck, you can use smaller (14ga or 16ga) wire as the amp's internal to the deck. If you want a power supply, let me know, I'm getting rid of a bunch of equipment at work and you could have one for the cost of shipping. I have converted a few of these to bench power supplies to test components (fans and the like).

[SuBrat84]

I'd never paid that much attention that a computer converts to DC. That is cool. I have an extra power supply sitting out in my yard.. I like the idea of it being a component tester. I just thought it would be kind of a bonus if something like that plug i could use as a free battery charger or in a "home" - "car stereo" system like they do in the stores that sell the junk. Thanks for the input thus far. Very informative. INPUT!!!