Even if you have an HDTV and a the necessary programming shooting through the airwaves, your run-of-the-mill VCR isn't going to do the format justice. Fortunately, many companies are working on gadgets that will let you record high-definition television and replay programs on your fancy TV in all their glory. At last week's CES , Zenith announced a high-definition, high-density video disc recorder (HD-VDR) featuring a built-in ATSC digital television tuner and offering about five times more data capacity than conventional DVDs. The HD-VDR was developed by Zenith's parent company, LG Electronics Inc. and is designed to record and play back more than two hours of digital HDTV programming. Zenith says the HD-VDR doubles as a digital set-top box that receives and demodulates digital HDTV signals using VSB (vestigial sideband) technology. The Zenith HD-VDR can record and play back high-definition video on a 23GB HD optical disc (about 5 times greater capacity than a conventional 4.7GB DVD). It also features an IEEE 1394 digital interface. Zenith plans to introduce the HD-VDR in 2003.