Re: Convert 12-14 vdc to 9 vdc for a device only needing 0.3ma...

Default User wrote:
Hi,

I've got a battery box with a 115AH deep cycle battery for power in a tornado shelter.

I had a thought that it would be nice to mount one of the cheap harbor freight $2 multimeters to it to monitor the voltage. They usually run on a 9 volt batter and consume a nice and small 0.3ma. What I don't know is if 12-14 volts would fry it or if it would do fine on that. Is there an easy (read cheap) way to drop the 12-14 volts down to 9 volts without increasing the power consumption very much?

Thanks,

Alan


Some multimeters cannot be powered from the source they are measuring. You may need a DC-DC converter to provide the necessary isolation.

--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P
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