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Sorry if this isn't the right place for this.

I have a Uniden UH015SX (https://www.uniden.com.au/resources_main/pdfs/uh015sx_OM_2yrWarranty-Updated.pdf) which requires 13.8v of DC power, but I'd really like to run it from my 12v DC aux power point in my car.

Is there any way to make this happen?

The only solution I can think of (and it's far from elegant) is to run an inverter and then a switchable DC supply set to 14v.

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You should be able to run the radio from your car.

The "12V" supply in a car is not very well controlled. It is just whatever the battery voltage is. When the car is running and the alternator is charging the battery it can be up to 14V. Given that 13.8V is often stated as the charging voltage for a car battery, I would assume that the 13.8V input is actually a "power from a car" input, and will happily take whatever the car is actually putting out.

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  • \$\begingroup\$ Multimeter reads 12.7 at it's max... I found this though: jaycar.com.au/Power-Products-Electrical/… \$\endgroup\$
    – LuckySpoon
    Apr 1, 2016 at 6:19
  • \$\begingroup\$ The radio looks like a unit designed to be installed in a vehicle. You really should try it before dropping more money on something that is almost certainly not needed. \$\endgroup\$
    – Austin
    Apr 1, 2016 at 7:05
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    \$\begingroup\$ @LuckySpoon - Just to be clear: Do not use either of the DC-DC converters on the page which you linked. One is designed to approx. halve the input voltage; the other is designed to approx. double the input voltage. Neither of those is correct for your CB! As Austin has said (+1), your CB is designed for use in a 12V vehicle. Re your comment about measuring 12.7V max - that is expected from a full 12V battery without the engine running. With the alternator running, the voltage will be higher (14.4V is common). Your CB (actually, any car electrics) is designed to cope with this. \$\endgroup\$
    – SamGibson
    Apr 1, 2016 at 10:58
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    \$\begingroup\$ @LuckySpoon - P.S. If you do some research, you will find that the "13.8V" specification for vehicle electrical accessories (e.g. radios) is known for just being a nominal voltage for 12V vehicle electrical systems. If you have more questions about vehicle electrical systems, there is another SE stack for automotive questions. \$\endgroup\$
    – SamGibson
    Apr 1, 2016 at 11:02
  • \$\begingroup\$ @SamGibson Thanks for the comment! I looked over the stack list and didn't see one for auto. I'll wire it up and see what happens, nothing too bad can come from under-voltage I'm sure. \$\endgroup\$
    – LuckySpoon
    Apr 4, 2016 at 1:26

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