I have an older TiVo Series 2 recorder. It says it will receive digital signal, but will not work now that the cable signal has turned to digital. The TiVo model is TCD540080. When I plug the cable directly into TiVo I don't get any signal. The only way I get signal is to go thru the analog converter box. If the TiVo says it will accept digital signal, why won't it work? is there anything I can do to get it to work without the analog converter?