As you know, the CRC broadcasters are scheduled to begin the transition of their affiliated stations from FM 2 to FM Quad as of November 1^st. Wegener Communications, in conjunction with the Christian Consortium, has been monitoring the Eb/No levels that radio stations have been reporting with the DVB carrier. Some stations have reported Eb/No readings fluctuating after the satellite dish was peaked with a spectrum analyzer. For example, a site may have low and/or fluctuating Eb/No readings even after aligning the antenna and minimizing the adjacent satellite/cross polarity interference.

After numerous discussions with Wegener, it was determined that an increase in power to the DVB carrier would improve the contrast ratio that currently exists between the FM 2 and FM Quad carriers. Wegener recently recommended that the contrast ratio to be no more than 14dB, however, the current level is 16dB. In order to improve this ratio, and to facilitate stations in making their transition to DVB, SpaceCom Systems increased the power into the DVB carrier on October 20, 1999.

I am informing you of this power increase because once your stations begin to migrate to the DVB carrier it will be extremely important that they peak the antenna with a spectrum analyzer to eliminate interference, both cross polarity and adjacent satellite and insure maximum gain is obtained. Failure to accurately peak each antenna could pose a problem on March 1^st when the power will be reduced to its specified level. As of March 1, 2000, the FM 2 carrier will be removed and the DVB carrier will be relocated more toward the center of the transponder. We expect this to improve the interference environment (reason for the temporary power increase) but are concerned that a number of downlinks may use the extra power to avoid accurate alignment during the conversion. These downlinks may experience a reception problem after the power normalization on March 1, 2000.

SpaceCom Systems