Cheap 12V DC bench top power supply

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moparmat2000

moparmat2000

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Was looking for a 12V DC power supply for doing light bench test stuff needing 12V DC like radios. Gage back lighting etc. Found a cheap 110AC to 12V DC inverter on evilbay. I think it's really for charging a computer. Anyways for $9 it was mine. I made a bracket out of scrap sheetmetal. Added a car charger, lighter plug, and 2 insulated lugs to attach alligator clip leads to it. Going to pick up a male lighter plug with 25 ft of cord which I will add alligator clips to. This will be perfect for testing isolated circuits like lighting in a car with battery unplugged, and connectors pulled apart. Will eventually add an on/off switch in the extra drilled hole, and attach it to the book shelf but for now will just unplug it. Easy project that adds versatility to your shop.

Hope ya like.
Matt

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moparmat2000 said:
Was looking for a 12V DC power supply fo doing bench test stuff needing 12V DC. Found a cheap 110AC to 12V DC inverter on evilbay. I think it's really for charging a computer. Anyways for $9 it was mine. I made a bracket out of scrap sheetmetal. Added a car charger, lighter plug, and 2 insulated lugs to attach alligator clip leads to it. Going to pick up a male lighter plug with 25 ft of cord which I will add alligator clips to. This will be perfect for testing isolated circuits like lighting in a car with battery unplugged, and connectors pulled apart. Will eventually add an on/off switch in the extra drilled hole, and attach it to the book shelf but for now will just unplug it. Easy project that adds versatility to your shop.

Hope ya like.
Matt

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Home made and handy. Well done. Those digital volt/amp displays are cheap and work well. I have some components ordered to make a pulse width modulator to control the heating element in my beer brewing equipment. Fun stuff. This one reduces voltage and measures amperage the load pulls. A/C only but works well for me.

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@kowalski440
 
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Hook a scope up to the output and take a look at the ripple. It would be interesting to see what that 12v output really looks like for $9. Also, what's the current capability of that thing?
 
I was thinking about this as redoing my garage for better function!

Good ideas!
 
toolmanmike said:
Home made and handy. Well done. Those digital volt/amp displays are cheap and work well. I have some components ordered to make a pulse width modulator to control the heating element in my beer brewing equipment. Fun stuff.
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Did you say BEER!
 
I have(somewhere) a 12 volt power supply i pulled out of a decommissioned mopar sound system display unit. They were chucking it out, so i snagged it.
Totally forgot i had it. Used it to power a car stereo i used as a shop radio for years.
 
It's a 5A rated supply. It wont power up high power stuff, but a car radio to test, maybe testing gage back lighting, and other small stuff, it's perfect.
 
You can make a high amp 12 volt and 5 volt supply out of an computer ATX power supply. They are in every desktop computer. They are often $1-5 dollars used at computer shops. Easy instructions on the web.
 
moparmat2000 said:
It's a 5A rated supply. It wont power up high power stuff, but a car radio to test, maybe testing gage back lighting, and other small stuff, it's perfect.
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A 5 amp supply isn't too shabby, you can do quite a lot with that much power. :thumbsup:
 
moparmat2000 said:
Was looking for a 12V DC power supply for doing light bench test stuff needing 12V DC like radios. Gage back lighting etc. Found a cheap 110AC to 12V DC inverter on evilbay. I think it's really for charging a computer. Anyways for $9 it was mine. I made a bracket out of scrap sheetmetal. Added a car charger, lighter plug, and 2 insulated lugs to attach alligator clip leads to it. Going to pick up a male lighter plug with 25 ft of cord which I will add alligator clips to. This will be perfect for testing isolated circuits like lighting in a car with battery unplugged, and connectors pulled apart. Will eventually add an on/off switch in the extra drilled hole, and attach it to the book shelf but for now will just unplug it. Easy project that adds versatility to your shop.

Hope ya like.
Matt

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I use a very old 12 VDC, 10 amp Sears battery charger
 
Heres a pic of what the inverter looks like. Also you can bench test a wiring harness for continuity with this and a light tester probe quicker than with a meter, unless your checking for resistance

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I like the Volt/ Amp meter.
I’m gonna put one in my motorhome to monitor my load(LOL)....
I’ll know when to charge my battery by monitoring the voltage drop.
 
69DodgeMan said:
Hook a scope up to the output and take a look at the ripple. It would be interesting to see what that 12v output really looks like for $9. Also, what's the current capability of that thing?
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You can also simply measure the ripple with a multimeter set to AC volts
 
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