Keith McMillen Instruments Batt-O-Meter Battery Tester  

Product #584403

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Item Note:

This product has been discontinued but may be available as a Open Box item.

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Shows the hours of life remaining on your stomboxes and active pickups without removing the battery.

Plug the Batt-O-Meter Battery Tester into virtually any battery-operated device with a 1/4" jack input and find out if and when to change its battery. Stop wasting time and money; don't guess when to change batteries; know with the Batt-O-Meter.

The Batt-O-Meter Battery Tester looks inside your active pickup instruments and 9-volt devices to measure voltage and remaining hours of use. Fast, accurate, and easy to use, the Batt-O-Meter: saves you from risk and stress of dead batteries before a performance. You'll also save money by extending the life of each battery, and save time by checking battery life before taking things apart. Feel better knowing that you're helping the environment by discarding fewer batteries.

The Keith McMillen Instruments' Batt-O-Meter also checks hard-to-reach batteries by plugging into the 1/4" input found on most guitars, basses and effects pedals.

Use the Batt-O-Meter battery tester to quickly and accurately measure how many volts a battery is delivering, the number of hours left before the power runs out, and the remaining life in any 1.5-volt or 9-volt battery. Just plug the gold-plated Power Probe into the 1/4" input on most instruments and effects pedals to test the life remaining in hard-to-reach batteries.

Test more battery types with increased precision with the Batt-O-Meter's convenient slide switch that differentiates between alkaline, rechargeable, and carbon zinc batteries. The right-angle, 1/4" jack can check a hard-to-reach battery still inside your equipment.

And, yes, Mr. Smarty Pants, the Batt-O-Meter performs a self-test of its internal battery and displays the percentage of battery life left.


Batt-O-Meter Battery Tester Specifications:

  • Requires 9-volt battery; not included
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by PowerReviews
Keith McMillen InstrumentsBatt-O-Meter Battery Tester

(based on 1 review)

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Reviewed by 1 customer

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Great Idea, Badly Implemented. Does not always work.


from Minnesota


  • Clear Display
  • Useful Display


  • Inconsistent Performance
  • Lacks Power

Best Uses

  • Avoid

Comments about Keith McMillen Instruments Batt-O-Meter Battery Tester:

I have a guitar with an after-market active EMG pickup, and when I saw this I got excited about the possibility of checking the battery without removing the cover plate. My bassist uses active pickups, so I bought two with the intention of one being a gift for her. Sadly, this unit has two major flaws:

1. It needs a battery of its own. Yep. It's a battery-powered battery checker. Why they wouldn't design it to be powered by the battery its checking is beyond me.

2. It doesn't work. The tip is an odd shape and so in many guitars (including mine) it will simply display "cable error" when trying to use the one feature that sets it apart from other battery testers. Apparently some people can get it to work with some pedals, but for the only reason I bought it (checking guitar batteries through the jack), it's useless.

I'm kind of tempted to cut the end off this thing and solder a standard 1/4" TRS connector to it. Or maybe I'll just return them both. If I need to DIY, an old guitar cable with an LED would probably be just as good if not better.

  • Primary use:
  • Personal
  • Was this a gift?:
  • No

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