Q: I have been hearing more and more about video over twisted-pair cable. Most of the information I can find has been on specific active equipment that converts the video signals to frequencies that can be transmitted over Category 5 cabling. Have there been any discussions by any committee of the Institute of Electrical and Electronics Engineers (ieee) or other standards body on a standard for video over twisted-pair?
Todd Harpel, rcdd
Hubbell Premise Wiring
Stonington, CT
A: Various passive balun products are available that allow baseband and broadband transmission of video signals over UTP. However, I am not aware of any standards activity to allow transmission of video signals over twisted-pair cable without active equipment.
Both ieee and Asynchronous Transfer Mode (ATM) specifications accommodate the digital transmission of video signals over twisted-pair cable without directly specifying the application. In addition, there are specifications (standard formats) for the analog transmission of video signals--both baseband and broadband--that can be implemented on twisted-pair.
For a good tutorial on transmitting video over UTP, see "Transmitting video over structured cabling systems," August 1995, page 51.