Odd output from ADXRS610

I’m using an ADXRS610 breakout board with an Arduino and I’m sampling the rate output of the gyro at 100 Hz. I’m sending the data to my laptop with an XBee pro.

Here is what I get:

http://lh3.ggpht.com/_Eogk12oYm-g/S0Qqy … llGyro.png

Does anyone have an idea about what’s causing the periodic bumps? I would have expected uniform noise.

I’m running the Arduino off of a battery and I added a 1 micro Farad cap across the gyro power. The cap seems to have no effect.

Perhaps the noise is from the Xbee? I’ll try it via direct connection. Is it related to this thread?

viewtopic.php?t=16672&highlight=gyro+noise

Thanks,

-Scott

** Update **

I hooked the Arduino up directly via USB (and removed the XBee) and I still see the same periodic disturbance. The period of the disturbance did, however, get a bit longer. Odd. Any ideas?