To all my distinguished colleagues. I wish to thank you for your responses to my call for help, and inform you of the finial outcome.
Some of you I have contacted directly and some I have not (due to time constraints) but I want to thank all that have responded very much. I have read and considered each reply. In summary, I was required to substitute a 10x10x22 ferrite tile chamber for a 10 OATS for emission pre-scan testing and needed fairly good correlation. To make a long story short here is what I did: The chamber had a metal floor that was naturally the major contribution to reflections. I placed ferrite tile square assemblies 2x2 Ft. from under the Biconilog running 3 meters to under the EUT table. The tile squares fanned out in the middle to form something like an oval. Now I have minimum reflections and once plotted gives me a curve very close to theoretical using a Biconilog and a Biconical antenna. The horizontal and vertical plot points fall all most on top of each other on the curve. I now have a ferrite tile tunnel, with only one major reflection at 150 MHz. which is stable and about 4 dB P-P. I am starting to test equipment which has returned for commercial labs and show a correlation of about 2.6 to 3 dB. Now this is not bad if I do say so myself. I only need to recheck the Field Uniformity, which I do not think will be adversely affected. Al Patrick, Sr. EMC Engineer - Manager of EMC Lab Operations Scientific-Atlanta Inc. al.patr...@sciatl.com 770 236 5148
