Addicted to data? $10 USB car charger with a voltmeter


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A voltmeter ought to built into anything with a battery, such as your VW camper. I built one into my Loud Bike. They can be had for $4 from China via Ebay.




plus it’ll show you the voltage drop when you’re pulling pulling 8 amps across the 14 gauge cigar lighter circuit :open_mouth:


So it’s a milliammeter too? Nice.

I always thought there should be cheap meters you could put between the wall plug and a device to show how much power it was using. They could save the info for you. (At the time I first thought of them, this wasn’t really an option, unless you wanted it to print it on paper.) I think I’d prefer that to having it transmit the info. Too many “things” are squealing on me already.


Surely a label, or color coding, or a robot monkey that starts clanging cymbals when the wrong plug is used could prevent this?


Not with a 9-year-old.


Maybe make her (?) push start it the next time she drains the battery?


Not with a 9-year-old.


wait 'til they’re 15, draining the starting battery will be a welcome relief.


I’d wire one one (and an Oil Pressure sensor) if I had anyplace that looked OK to mount extra gauges in the Vanagon. This just goes in the lighter socket and all is well.

Someday I’d like to build that out.


as my then-6-year-old once made crystal clear:
My in-dash 6 CD changer hungers - HUNGERS I TELL YOU - for the taste of random coins that would have otherwise been simply thrown out the window (at a toll collection point)


For me its the cigarette lighter socket which is mounted vertically in my wife’s Jetta, and is right beside the ash tray. I threw the lighter away and we throw coins in the ash tray. The resulting accidental short circuit blew something up in the VW’s electrical system without blowing a fuse. Cost quite a bit to repair.

Now I have a USB power supply permanently installed in that socket.


At around 2 she fed a $1 bill into the DVD-R on my iMac.

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