Hi, A couple months ago I bought a 3-axial gyro from ebay. I've looked everywhere for its datasheet and couldn't find any information. It is (was) manufactured by Northrop Corporation (see info below). NORTHROP CORPORATION Precision Product Division FSC 51834 Mfr. P/N: 50162-317 3 AXIS DC/DC GYRO PKG. P/N 50162-317 SER.NO 104 WT. 1,8 LB This is extracted directly from its ID label. I contacted several departments at Northrop-Grumman, and thanks to their friendly effort, I was told that the division where this product was manufactured was bought by Allied Signal that was bought by Honeywell. I even spoke with the gal at Honeywell that works in the department that was supposedly responsible for it, but she said the part was too old and there was no documentation about it. Now my only hope is to start experimenting with it. I opened the box to check what is inside. The device has a 10 pin military circular connector from which only 8 pins are connected. Two of the wires, one red and one black are a bit thicker and I assume are VCC and ground, the others should be signal wires for each axis. There is a sealed black box (impossible to open without damaging) where all electronics reside (that's why I suspect it is a military device). There are also two metalic cylinders in one horizontal axis, a smaller on another orthogonal horizontal axis, and a small one on the vertical axis. My first test was supplying 12V and monitor the other pins on the oscope. I couldn't find out much, except that there is a very soft high-pitched sound, and a weird waveform coming out of the pins. They didn't change as I rotated the gyro around. Somewhere I read that avionics (which I suspect this gyro was originally used for) use 24VDC, but before I started venturing in! creasing the voltage on my power supply and see white smoke out of the device, I found better to ask first in case anybody has a suggestion. What is the overal way to operate an [old electromechanical] gyro like this? In what form should I expect the signal to vary when I turn the gyro in one axis, DC level, waveform, differential? I think this is my last try on finding any info before I try to hack it and possibly burn it. So I appreciate any hint you may have. Cheers Padu -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist