On Mon, 26 Mar 2012 12:08:43 -0700, "William Sommerwerck"
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.

You mean useless. If it were dead...

It's a common design problem. How does one provide an active
indication that the power source is dead, when the indicator is
powered by the same power source. The usual "solution" is to have the
indicator proclaim a dead battery, long before the device ceases to
function. My HP calculators mostly do it that way. I can run them
for months with the dead battery indicator showing.

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.

This is Most Amusing, because I was checking a pile of NiMH AA cells, and
most of them read a few tenths of a volt. Then, a few hours later, they were
all fine.

Ummm... I don't think that's the result of a low battery in your Fluke
78. My 77 is similar and simply produces modest errors before it
quits completely. A few tenths of a volt is a rather drastic error.
Check the probes?

In case you're wondering... Of course I use an alkaline battery. A lithium
would be an even better choice. MCM has name-brand lithium 9V batteries for
about $5 right now.

Cool. I need some other parts from MCM. Thanks.


--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
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