The vertical blanking period is an idle period in video transmission that was originally intended for allowing the trace back of an electron beam to its point of origin. When sending the video signal over a wireless channel, the wireless channel may remain free of transmission of data during this period. However, in wireless transmission of a video signal in general, and in the transmission of an essentially uncompressed video signal in particular, there is a need to use all the bandwidth available, especially when transmitting a high-definition video signal. Therefore, a method is taught for using the vertical blanking period of a video signal for modem maintenance.