Battery dying too quickly... why??

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1

I have had my m240 for about a year and have been pleased with its performance.  Over the past week or so, the battery seems to be dying prematurely.  When it first happened, I thought that maybe I forgot to shut it off and the battery ran down.   However, I replaced the battery and after 1-2 hours of use, I got the “low battery” message on the screen.   What is happening?  Surely, I don’t have a bad batch of batteries.  I recently bought them.   Your help will be appreciated.

Al

2

I have a new m240. I just made some current draw measurments with a Fluke 111 multimeter. When the player is off, I can’t see any current flowing. It might be drawing a few microamps, but the smallest current this meter will measure is 1 milliamp, which can also be expressed as 0.001 amp or 1000uA (1000 microamps).

When the player is first booting, it draws close to 100mA (miliiamps) or 0.1 amp.  Sitting idle in “play audio” mode, it draws about 34mA (0.034 amp). When the LCD backlight is on, current draw is about 45mA. When playing music at wide open volume, the current varies from about 35mA to 55mA.  In FM radio mode, the idle current is slightly higher, about 52mA. It draws up to about 65mA at full FM radio volume. This means the battery will last slightly longer playing mp3’s than it will when receiving FM radio. These readings were taken with the supplied ear buds.

Do you have access to a multimeter? If so, connect the negative side of the AAA battery to the negative contact spring in the player. The positive (red) lead of the current meter connects to the positive cap on the AAA battery. The negative (black) lead of the current meter connects to the positive contact point in the player. Basically, you need the current to flow through the current meter for the test. If your m240 is drawing current in it’s “off” mode, there is something wrong with it. Is the backlight staying on all the time? If so, that would only make the battery life drop about 30%. Maybe your player is drawing a lot more current than it should.

Are you using quality batteries? Brand name alkalines should last at least 15 hours, 800mAh NiMh rechargeables should go 10-12 hours. Cheapie zinc-carbon batteries will only last about 5 hours at the most. I discovered that because I got 3 of these “Eveready heavy duty” AAA’s with an LED flashlight. I used them in my m230 and they only made it through a couple 2 hour talk show podcasts.  

I don’t know of an easier way to test this accurately. Another simple test would be to check a battery in a battery tester, note the meter reading, then put it in your player. Let it sit for a day without turning it on, then test the battery again. If it reads lower, the player is drawing current when it’s off.

Good Luck! 

Message Edited by MinimaxMan on 08-23-2007 01:50 PM

Message Edited by MinimaxMan on 08-23-2007 01:53 PM