From: "Chuck Derrow" <[email protected]> Subject: EMC test set-up question
Hello, Our company sells CO based telecommunications testing equipment. Currently we are re-testing our central controller which lives in a service center / office complex. This equipment has several rack mount modems which terminate inside our cabinet on Krone blocks. For EMC testing we generally connect a couple of 25 pair cables to the blocks in an effort to simulate the installed application where there are live phone line connected to the modems. As I get ready for re-testing due to other changes in the system, IUm seeking opinions on this Rphone line installation simulationS . 1) Should the attached 25 pair cable be terminated into 600 ohms or left open for a true simulation. Every phone line attached in the real application will terminate into a line card in a switch, 600 ohms. 2) There are also 48 RS232 ports available in the system for user terminals. Currently we connect cables until no change is seen in the radiated measurements of the system. Should these lines be open ended or have some sort of termination ? I would appreciate any opinion you may have or experience you could share. Regards, Chuck Derrow Sr. Compliance Engineer Teradyne, Telecommunications Div. [email protected]
