Proper Battery Voltage

Discussion in 'Miscellaneous [BG]' started by SuperDuck, Dec 6, 2001.

  1. SuperDuck


    Sep 26, 2000
    At my work we have tons of 9 volt batteries for use with our wireless mics. At the bottom of the mic there is a light that turns yellow when it's time to change the battery. You can get a decent amount of time out of them before they die, but we throw them out right when they turn yellow, so we aren't caught in the middle of a show with a dead or crackling mic.

    Anyway, after considering the price of 9 volts, I figured I would just take them home with me, since they are going to be thrown out anyway. The thing is, they are worn out a bit. Would I be wasting my time? When I go into work the next time I'll whip out the ol' multimeter and see what kind of voltage these batteries have left at "yellow". What's an acceptable charge for an active bass?
  2. Use Lithium-ion batteries.
  3. U can't measure it with a mulitmeter just across the terminals. It would probably read 8.88 volts or something and you'll go "yep thats ok". But you will be putting a load on the battery when u use it in the bass.

    The best thing to do would be get a 100 ohm resistor, put it across the battery terminals and measure the voltage across the resistor. It can be any value really, you just have to create the load. I have found 9 volt batteries that measure 8.7 volts without load can measure 4 volts with load.

    My mum works as a asthma researcher and one of the measuring devices run off a 9 volt battery. Because it is medicine and the results need to be spot on, they put a 9 volt battery in, use it for that patient visit and then throw it out. most of these visits are only an hour long. So the batteries are fresh. Ahh governments and spending!

    I would think any battery between 7 and 9 volts would be ok for a active bass. if u can get your hands on them easy be really picky.


  4. SuperDuck


    Sep 26, 2000
    Bah, it was late and I was using a multimeter that night at work... I meant battery tester. We have one that measures 9v and other battery types.