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Author Topic: 9V PP3s...  (Read 524 times)
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Johannesburg. UTC+2
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Useless bloody things... I think it's flat already.


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Roy from ITCrowd: Have you tried turning it off an on again?
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Leighton Buzzard, UK
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wow an electric slide rule
shame about the battery though!
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there are only 10 types of people
them that understands binary
and them that doesn't

Anchorage, AK
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I have a wireless transmitter for my bass that uses 9v batteries.  When I was actively playing in local bands, I would go to a gig with a fresh one in the body pack, and a spare in my case.  If there was anything left in the battery after the gig, I would use it up at our next practice.  In comparison, my wireless receiver (for monitoring) used two AAs and would last for hours and hours and hours.

I tried using NiMH rechargeable 9v cells, and I'll tell you this... it's no wonder they're hard to find.  They make alkaline 9v cells look like an endless fountain of energy.  I just gave up when the top cap came off one of the cells trying to unplug it from the charger.  Totally useless.
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Yes.  There was an old App-note from Linear technology that pointed out that 2*AA batteries contained significantly more energy, at less cost and about the same space, as a 9V battery.  ESPECIALLY if you were going to regulate your 9V down to 5V with a linear regulator, and used their new switchmode converter chip to step the 3V UP to 5V instead.

Those smoke detectors that run 1year+ off a 9V battery are engineering marvels!
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Quote
Those smoke detectors that run 1year+ off a 9V battery are engineering marvels!

So are Fluke DMMs....

Tom..... smiley
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Everything runs on smoke, let the smoke out, it stops running......VK3DMK

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