By Nate Levine,Vice President, Engineering, Sammons Communications, Inc.
Most of us who operate cable systems and are providing twelve channels of service to our customers at a fixed fee have probably considered, at one time or another, the possibility of adding several additional channels in the mid or super band frequency range, providing converters to customers who desire these channels and charging an additional $2-$3 per month for this service. At the onset, this does not look like a difficult task since most cable systems today already have the necessary bandwidth to carry mid band frequencies and most new systems being installed today have extended bands with widths of 260 or even 300 MHz.
At this point in time, it should be apparent to most of us that this should . only be attempted on systems where second order distortion is at a minimum, such as a push-pull system. For the purpose of this presentation, we will assume that second order problems are non-existent and explore the other problems that arise when mid band and super band channels are added.