 In order to make them work with DTV the viewer must use an external tuner box and set the device to record the output from that box, typically L-1 for the line input.Some manufacturers such as Zinwell and Dish sell external converter boxes/tuners that will automatically change channels at preset times.The analog VCR or DVR may record at preset times but will continue recording the L-1 line input, which will be the same channel unless the channel is manually changed.