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Jeff Liebermann Jeff Liebermann is offline
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Default Anyone know a DVM exorcist?

On Mon, 26 Mar 2012 12:25:13 -0500, Jim Yanik
wrote:

doesn't it have a LOW-BATT indicator on the LCD screen?


Yes. The Fluke 77 has a rectangular battery symbol in the upper left
corner of the screen. When it comes on, the battery is certainly
dead. However, voltage measurements go insane somewhat before the
indicator comes on. I was checking my supply of AA alkalines in the
fridge and noticed that I was tossing far too many batteries as dead.
I checked the readings with another DVM and found that the Fluke 77
was erratically reading about 300mv low. The battery indicator never
came on. When I replaced the battery, the readings returned to
normal. I don't recall if the flashing display happened before or
after the battery indicator.

That was with an alkaline 9V battery. I'm tempted to spend the $7.00
and get a "smoke alarm" lithium battery such as an Ultralife:
http://ultralifecorporation.com/be-commercial/products/9volt/

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