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power a 12 volt dc car radio by using a 110 ac laptop power cord?

power a 12 volt dc car radio by using a 110 ac laptop power cord?

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  #1  
Old 07-19-15, 11:39 AM
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power a 12 volt dc car radio by using a 110 ac laptop power cord?

I'm hoping there is a way to hook up a car radio inside a house. I was thinking that I could use a power cord leftover from an old laptop to convert the ac to dc? If that is possible, I wouldn't know how to get the part that plugs into the laptop to convert to either a cigarette lighter receptacle or just 2 plain bare wires? Is this possible or do I have to buy a converter?
 
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  #2  
Old 07-19-15, 11:59 AM
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First be sure that the laptop charger delivers enough current (stated as amperes or watts) needed to operate the radio. The be sure that the voltage is correct, which for a car radio 11 to 14 volts DC will work okay.

Such a power cord is not just a cord. It has a block, perhaps the size and shape of two cigarette packs end to end, in the middle that is a voltage converter.

Yes you could cut off the little plug that fits into the laptop, leaving two bare wires that you can connect to the car radio.

Using a multimeter or a DC voltmeter, verify which bare wire end is positive and which is negative to connect to the radio.
 
  #3  
Old 07-19-15, 12:26 PM
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It won't be a red and black wire once I cut into the cable? Maybe I can borrow a meter like you mention. This is going to be a surprise for someone's home mancave. He is a truck driver and has a 'radio box' that he used in his truck. It has a cb and radar detector also, but he wouldn't be using those, just the am/fm radio so I don't think it would need very much power and therefor I thought the laptop cable would be the answer. It will be a big surprise he would never expect from me.
 
  #4  
Old 07-19-15, 08:32 PM
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Until you cut the plug off the wire colors are unknown. Before you cut the plug off..... make sure the adapter says 12-14vdc on it. Most laptop adapters are 15vdc and higher and can damage the radio.
 
  #5  
Old 07-20-15, 03:19 AM
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ok, I didn't realize they were all different. I'll definitely check both the radio and the laptop plug.
 
  #6  
Old 07-20-15, 08:24 AM
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Oh yes, they're all different. The AC adapter for my Toshiba laptop puts out 19 volts. Sometimes even the adapters for different models of the same computer brand are different. The adapters aren't cheap either; you might be better off trying to find a simple 12 vdc power supply.
 
  #7  
Old 07-20-15, 02:01 PM
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Other things to consider: is there an antenna connection? My guess you won't get very good reception without one. Also most radios have special adapters to connect to amps and speakers in vehicles. The connections may not be as simple as what you might expect unless you relish building a home stereo system from scratch. What speakers do you have to connect this to? You might need an additional amplifier depending on what speakers you connect to it.

- Peter
 
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Old 07-20-15, 02:10 PM
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About 40 yrs or so ago I bought a 120 volt ac to 12 volt dc converter, years later when I built my shop I hooked an old car radio to it and used it for maybe 10 yrs in my shop. I did have a car antenna hooked to it. It needed no amplifier but then I'm not big on loud music. I'd probably still be using that set up except I inherited a radio shack tuner which I now use instead.
 
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Old 07-21-15, 06:15 AM
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FWIW, an old computer power supply will also work. When the radio in my garage/woodworking shop died, cheap guy that I am, I cobbled one together with an old PS and a car radio.
 
  #10  
Old 07-22-15, 04:50 AM
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I didn't realize that the toshiba laptop power cord was so different than others manufactured by them. I knew the plug sometimes were different for each model laptop, but I never realized the power was different. Now that I give it some thought I guess they would have to be different depending on the power requirements . I was hoping to do just what was mentioned about using the car radio in the shop. I have an old dell desktop. Is it better to think about using the power supply from that, or should I just buy an ac/dc converter that is made for what I am trying to do? What happens if I use a laptop cable for a laptop and it is underpowered, does the laptop just run slower or would it not run at all? Or, if I used a cable that was over powered, would the screen be brighter?
 
  #11  
Old 07-22-15, 06:18 AM
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You've got me confused. I thought you were looking to use a power supply from a laptop to power the radio.

You do want to match the laptop lower supply to the laptop. Under power (right volts but less watts) may prevent the laptop from running. Too many watts won't hurt at all. The laptop manufacturers do a good job of using specific connectors so it is a challenge to actually use the wrong power supply unless you are using a"universal" style.
 
  #12  
Old 07-22-15, 07:54 AM
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that is correct, I am trying to figure out the power cable to be able to run the car radio. I got a little side tracked with the laptop to laptop question. I was wondering out loud what would happen to the laptops as opposed to the radio. If I have too much power or if I had too little power. I just figured the laptop or the car radio would just take the power it needs if the supply was over powered and leave the rest, with no damage done, or if it were under powered, I didn't know how to ask the question as how to apply it to the car radio, so I asked it for the laptop.
 
  #13  
Old 07-22-15, 08:18 AM
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My very own first "home" stereo was the Pioneer Supertuner from my car. It was on a slide-out mount and went with me into the dorm. Back then CB radio was big and every store had 12V power supplies.

Knowing what I know today I would grab a used "office" mini stereo from a Salvation Army thrift store for under $50 and not bother with the hum from the converter and the jumper wires.
 
  #14  
Old 07-23-15, 04:00 AM
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yes, I think I am going to abandon the idea and come up with something else, unrelated. I found a Wurlitzer juke box that I might be able to fix up. It works but is rusty and needs some cleaning up.
Thank you all for the advice and technical assistance. It kept me from trying something that was more complicated than I thought.
 
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